Two days ago, only one sportsbook had theas 4-point favorites, while everyone else held the line at -3.5.
As of Sunday morning, almost every sportsbook was there and one UK-based shop at -4.5.
"We had the line at -4 because we felt that's where the line would eventually settle and we were ahead of the curve a bit on that," said Kevin Bradley of Bovada. "We have evenly split action on both the 49ers and Ravens so we do not anticipate a move to -4.5 this late in the week."
Indeed Bovada has been sitting at -4 all along and late action on the 49ers has forced the hand at other Vegas and online sportsbooks which had the spread at -3.5 for nearly two weeks. [ Full matchup deals and picks ]
Unlike previous Super Bowls where the sportsbooks were in danger of a huge loss on Super Bowl bets, the 2013 edition of the game appears to be a safer situation. Some shops have some exposure to a Baltimore victory on the moneyline and some have a few big payouts to make on futures.
"We need the 49ers who would be a big winner for us," Bradley said earlier in the week about some 18/1 and 20/1 bets made early in the playoffs.
"And theended up over the last couple week turning into a big potential loser for us."
Ladbrokes, a UK-based sportsbook, was the only one of 20 shops tracked by OddsShark.com at -4.5 as of Sunday morning.
Check out the latest Super Bowl odds here at SBNation.