The underdog\n\n A plus sign (+) in front of the handicap indicates an underdog. The 49ers are the +1.5 underdog in this game, meaning oddsmakers believe they will lose, but only by a point. To win this point spread bet with the 49ers, San Francisco would need to win the game outright or lose by one point exactly.
This Share. When betting on an MLB run line, +1.5 means that the underdog team must either win the game outright or lose the game by one run or less in order for the bet to be successful. With a run line, also called against the spread,  the spread is almost always 1.5 runs.