Lately, pundits and punters seem bullish on Donald Trump, whose chances of winning the Republican presidential nomination recently inched above 20 percent for the first time at the betting market Betfair. Perhaps the conventional wisdom assumes that the aftermath of the terrorist attacks in Paris will play into Trump’s hands, or that Republicans really might be in disarray. If so, I can see where the case for Trump is coming from, although I’d still say a 20 percent chance is substantially too high. 
 
 Quite often, however, the Trump’s-really-got-a-chance! case is rooted almost entirely in polls. If nothing Trump has said so far has harmed his standing with Republicans, the argument goes, why should we expect him to fade later on? 
 
 One problem with this is that it’s not enough for Trump to merely avoid fading. Right now, he has 25 to 30 percent of the vote in polls among the roughly 25 percent of Americans who identify as Republican. (That’s something like 6 to 8 percent of the electorate overall, or about the same share of people who think the Apollo moon landings were faked.) As the rest of the field consolidates around him, Trump will need to gain additional support to win the nomination. That might not be easy, since some Trump actions that appeal to a faction of the Republican electorate may alienate the rest of it. Trump’s favorability ratings are middling among Republicans (and awful among the broader electorate). 
 
 Trump will also have to get that 25 or 30 percent to go to the polls. For now, most surveys cover Republican-leaning adults or registered voters, rather than likely voters. Combine that with the poor response rates to polls and the fact that an increasing number of polls use nontraditional sampling methods, and it’s not clear how much overlap there is between the people included in these surveys and the relatively small share of Republicans who will turn up to vote in primaries and caucuses. 
 
 But there’s another, more fundamental problem. That 25 or 30 percent of the vote isn’t really Donald Trump’s for the keeping. In fact, it doesn’t belong to any candidate. If past nomination races are any guide, the vast majority of eventual Republican voters haven’t made up their minds yet. 
 
 It can be easy to forget it if you cover politics for a living, but most people aren’t paying all that much attention to the campaign right now. Certainly, voters are consuming some campaign-related news. Debate ratings are way up, and Google searches for topics related to the primaries have been running slightly ahead of where they were at a comparable point of the 2008 campaign, the last time both parties had open races. But most voters have a lot of competing priorities. Developments that can dominate a political news cycle, like Trump’s frenzied 90-minute speech in Iowa earlier this month, may reach only 20 percent or so of Americans. 
 
 We can look deeper into the Google search data for some evidence of this. In the chart below, I’ve tracked the aggregate share of primary-related searches in the 2008 and 2012 presidential cycles, based on the number of weeks before or after the Iowa caucuses. As you can see, public attention to the race starts out quite slow and only gradually accelerates — until just a week or two before Iowa, when it begins to boom. Interest continues to accelerate as Iowa, New Hampshire and the Super Tuesday states vote, before slowing down again once the outcome of the race has become clear. 
 
 To repeat: This burst of attention occurs quite late — usually when voters are days or weeks away from their primary or caucus. At this point in the 2012 nomination cycle, 10 weeks before the Iowa caucuses, only 16 percent of the eventual total of Google searches had been conducted. At this point in the 2008 cycle, only 8 percent had been. Voters are still in the early stages of their information-gathering process. 
 
 When should you start paying attention to the polls? 
 
 But maybe you don’t trust the Google search data. That’s OK; exit polls like this one have historically asked voters in Iowa and New Hampshire when they made their final decision on how to vote. These exit polls find that voters take their sweet time. In Iowa, on average, only 35 percent of voters had come to a final decision before the final month of the campaign. And in New Hampshire, only 29 percent had. (Why is the fraction lower in New Hampshire than in Iowa? Probably because voters there are waiting for the Iowa results before locking in their choice. In fact, about half of New Hampshire voters make up their minds in the final week of the campaign.) 
 
 SHARE OF IOWA VOTERS WHO DECIDED ELECTION > 1 MONTH OUT 1 WEEK TO 1 MONTH OUT FINAL WEEK 2004 Democrats 30% 27% 42% 2008 Republicans 28 31 40 2008 Democrats 49 24 27 2012 Republicans 32 21 46 Iowa Average 35 26 39 SHARE OF N.H. VOTERS WHO DECIDED ELECTION > 1 MONTH OUT 1 WEEK TO 1 MONTH OUT FINAL WEEK 2004 Democrats 26% 19% 54% 2008 Republicans 29 22 50 2008 Democrats 34 17 48 2012 Republicans 28 26 46 New Hampshire Average 29 21 50 
 
 By comparison, voters decide much earlier in general elections. In Ohio in 2012, for example, 76 percent of voters had settled on Mitt Romney or Barack Obama by the end of September. This is why it’s common to see last-minute surges or busts in nomination races (think Rick Santorum or Howard Dean), but not in general elections. 
 
 If even by New Year’s Day (a month before the Iowa caucuses, which are scheduled for Feb. 1) only about one-third of Iowa voters will have come to their final decision, the percentage must be even lower now — perhaps something like 20 percent of voters are locked in. When you see an Iowa poll, you should keep in mind that the real situation looks something more like this: 
 
 CANDIDATE SUPPORT IN IOWA Undecided 80% Donald Trump 5 Ben Carson 4 Ted Cruz 3 Marco Rubio 2 Jeb Bush 1 Carly Fiorina 1 Mike Huckabee 1 Chris Christie 1 
 
 So, could Trump win? We confront two stubborn facts: first, that nobody remotely like Trump has won a major-party nomination in the modern era. And second, as is always a problem in analysis of presidential campaigns, we don’t have all that many data points, so unprecedented events can occur with some regularity. For my money, that adds up to Trump’s chances being higher than 0 but (considerably) less than 20 percent. Your mileage may vary. But you probably shouldn’t rely solely on the polls to make your case; it’s still too soon for that. 
 
 Read more: “The Perfect Republican Stump Speech” ||||| Yes, I know: There’s an incredibly handsome orange-haired man from Queens sitting atop the polls. Donald Trump has a serious chance of winning the Republican nomination — not words I’d have expected myself to be writing six months ago. Ted Cruz and Marco Rubio, however, still have a shot to knock Trump off his pedestal. Jeb Bush, John Kasich and Chris Christie might have a chance too, although they’ll need a lot of things to break right for them. 
 
 The dominoes will begin falling after the Iowa caucuses Monday night. It seems to me there are four basic narratives that could emerge from the state. (By “narratives,” I mean how the media, Republican party elites and the other candidates will interpret the results. Be warned: How the media responds is sometimes way more predictable than how voters do.) They depend, respectively, on whether Trump beats Cruz and on how well Rubio does. 
 
 About Rubio: What it means to perform “well” is obviously a little subjective, but how a candidate does relative to his polls is usually a pretty good guide to the spin that eventually emerges. Recent Iowa polls have Rubio in third place, with a vote share in the mid-teens. If Rubio finishes in the low teens or worse, his performance is likely to be regarded as disappointing (he’ll also be at risk of falling behind Ben Carson or another candidate into fourth place). If he’s in the high teens or better, he’ll probably be regarded as having momentum, especially if he slips into second place. Our models also think there’s an outside chance — 7 percent to 10 percent, depending on which version you look at — for Rubio to win Iowa. That’s mostly out of an abundance of caution: Iowa polls are sometimes wildly off the mark. The scenarios below contemplate Rubio finishing in second or a strong third place, but not winning. Of course, there could be even crazier outcomes still — our models give Carson around a 1-in-100 chance of winning Iowa, for example — but the four cases we describe below are the ones we take to be most likely. 
 
 Road No. 1: Trump beats Cruz, and Rubio does well 
 
 This seems to be the result the cognoscenti are expecting. Betting markets give Trump a 2-in-3 chance to win Iowa; our models now have him favored too, although not by as clear a margin as the markets. Meanwhile, there’s a lot of talk, with some justification, that Rubio has “momentum” going into the caucuses. 
 
 No matter what happens, the first headlines that emerge from Iowa are likely to be about Trump. Depending on exactly how well Rubio does, however, the conventional wisdom could congeal into anticipating a two-man race between Trump and Rubio. Perhaps that’s the matchup Republicans deserve. Rubio and Trump offer the two clearest visions for what the Republican Party’s future might look like: a forward-looking but emphatically conservative party in Rubio’s case, a populist-leaning and perhaps radically changed one in Trump’s. 
 
 It’s also the matchup that Republican “party elites” seem to want. By mounting an anti-Cruz campaign in Iowa, they were necessarily helping Trump, perhaps on the theory that another candidate could emerge to defeat Trump later on. If Rubio performed well in Iowa, he’d look like that candidate, giving party elites as good an outcome as they had any right to expect. 
 
 The big caveat is that this was possibly an idiotic strategy to begin with; it’s nearly impossible to control either Trump or the media narrative surrounding him, and it might be even harder after a big win in Iowa. We’d want to look for active signs of party leaders moving toward Rubio — in the form of endorsements and explicit pressure on candidates like Bush to drop out of the race. If Republican bigwigs just sit passively golf-clapping the result instead, the Trump whirlwind could sweep the news about Rubio’s vaguely good finish off the front pages. 
 
 Road No. 2: Trump beats Cruz, and Rubio does poorly 
 
 Get your Drudge Sirens ready. If Trump not only wins but blows out the competition, with both Cruz and “savior” Rubio flopping, Monday will be one of the most famous days in American political history. Although there might be some hope of anointing a new savior in New Hampshire — Bush, Kasich or Christie — other party elites might begin to capitulate toward Trump, as is already happening to some degree. 
 
 Could Trump get off to an extremely strong start, winning the first several states along with most of those in the “SEC Primary” on March 1, only to fail later on? Well, perhaps. The GOP calendar backloads a lot of winner-take-all or winner-take-most primaries in blue and purple states into April and beyond, so Trump could emerge with huge amounts of momentum but not be anywhere close to mathematically clinching the nomination. To some extent, we’d be in uncharted territory, since a Trump-like candidate has never gotten off to such a strong start before. But for Trump to lose, someone would have to beat him, and if both Cruz and Rubio blew their chances, it’s hard to know which candidate that would be. In my view, it would be safe to say that Trump had become the odds-on favorite to win the nomination, but where he’d fall on the spectrum between 51 percent and 99 percent I’m not sure. 
 
 You might notice I’ve pulled a little trick there, however, presuming a “blowout win” for Trump when that wouldn’t necessarily be the case. Suppose Rubio did badly, but Trump only narrowly beat Cruz. Would that make a difference? My guess is that it wouldn’t make a lot of difference — a Trump win is a Trump win — unless the vote were so close that (as in 2012) the outcome was uncertain well after midnight. 
 
 But this is one of the trickier cases. Cruz’s campaign would point toward how it had beaten expectations despite “the establishment” having stacked the deck against it. Which would be a pretty reasonable argument! But that doesn’t mean that Republican elites, having registered their discomfort with Cruz, would be receptive to it. 
 
 Road No. 3: Cruz beats Trump, and Rubio does poorly 
 
 If Cruz beats Trump, however, Cruz will look Teflon, and the Republican elites who tried to stop him will seem feckless. Also, since the conventional wisdom no longer anticipates a Cruz win in Iowa, it will be more surprising and possibly produce a bigger Cruz bounce. Furthermore, suppose that Rubio has a poor night. This is the nightmare case for Republicans who were hoping to stop Cruz. 
 
 It would also make New Hampshire really interesting. Trump begins with a fairly large lead there, and Cruz is not a good fit for the state. So even a fairly large bounce for Cruz (and an erosion in Trump’s support) could leave both candidates stuck in the high teens or low 20s, not necessarily enough to win. It’s possible that someone like Kasich or Bush could emerge under those circumstances. 
 
 We’d also want to look for signs of whether Cruz’s win in Iowa was an indication of Cruz’s strength or Trump’s weakness. If it seemed to be a result of Trump’s failed ground game, maybe that wouldn’t be as much of a problem for Trump in New Hampshire and other primary states, where the barriers to participation are less than in a caucus. Nonetheless, Trump would be — for the first time all campaign — a loser. To the extent his support is partly based on a bandwagon effect, it would be seriously tested. 
 
 Road No. 4: Cruz beats Trump, and Rubio does well 
 
 If both Cruz and Rubio have strong nights in Iowa, however, the meaning is clearer: Trump didn’t live up to the hype. There would be questions about whether Trump’s support in polls was a mirage to begin with, whether it had collapsed at the last minute because of voter dissatisfaction with his having skipped the Republican debate, or whether his lack of a turnout operation had foiled him. Those questions would be important for determining whether Trump had a chance to recover in New Hampshire. But in terms of the media narrative, they’d all be variations on the theme that Trump had gone bust. 
 
 In some ways, the Republican primary might even start to look fairly conventional. An “outsider” candidate with evangelical support would have won Iowa. A couple of “insider” candidates would be looking to emerge out of New Hampshire, with Rubio having a leg up because of his strong Iowa showing. Trump wouldn’t necessarily disappear — the media will keep writing him into the plot so long as he is willing — but it might be as more of a Newt Gingrich-esque sideshow, a candidate who wins a few states here and there but has little chance of commanding a majority. If we enter Iowa in a Trumpnado and exit it with what seems to be a fairly normal Republican race, that might be the biggest surprise of all. 
 
 Read more: 
 
 Four Roads Out Of Iowa For Republicans 
 
 What Happens If Bernie Sanders Wins Iowa 
 
 Listen to the latest episode of the FiveThirtyEight politics podcast.
– The Iowa caucuses are here, and Nate Silver, who wasn't expecting Donald Trump to still be leading the GOP field at this stage, still thinks he could be knocked off his perch. At FiveThirtyEight.com, the predictions whiz outlines four possible results in Iowa—and four ways the media is likely to spin them. Marco Rubio as the GOP's Savior. If Trump beats Ted Cruz and Rubio does well, expect the GOP elites to rally behind Rubio, Silver predicts, adding that in what was "possibly an idiotic strategy," the GOP establishment may have had this outcome in mind when it launched recent attacks on Cruz. A Trump Blowout. If Trump beats Cruz and Rubio flops, Monday "will be one of the most famous days in American political history," according to Silver, who predicts that a blowout Trump win would make him the odds-on favorite for the nomination—and leave the GOP without a clear alternative. Cruz in Control. If Cruz beats Trump and Rubio has a bad night, "Cruz will look Teflon" and it will be a nightmare for the GOP elites who opposed him, Silver writes. He predicts that a post-Iowa Cruz bounce could open up chances for Jeb Bush or John Kasich in New Hampshire. A Trump Bust. If Cruz beats Trump and Rubio has a strong night, the story will be all about a Trump bust, whether or not his New Hampshire chances still look good, Silver predicts. He notes that a Trump collapse would leave the GOP primary looking relatively normal, which "might be the biggest surprise of all." Click for Silver's full column.