The answer here is maybe a little surprising - it's more often than not! That's the benefit of a spread bet, is that it gives the underdogs a chance even when they're unlikely to win the game. Prior to the rapid expansion of legal online sports betting in North America, the underdog covered the spread a little over 54% of the time. Since 2018, that number has dropped by about a percentage point to the mid 53% range, which is still quite good.