A 1.5 point spread can mean two different things in baseball betting. It depends on whether it has a plus sign or a minus sign before the number. By the way, point spreads are often referred to as run line spreads in baseball. A -1.5 run line spread means you are betting on the favorite to win the game and they must win by at least 2 runs or more for you to win your bet. The opposite can be said when it's a +1.5 run line spread. This means you are betting on the underdog for the game. And they must only lose by a single run or straight up win the game, for your run line spread bet to win.