The San Francisco 49ers are underdogs later today when they host the Denver Broncos, but professional bettors have been intrigued by SF all week. The line for the game opened as high as Broncos -6, but it has been bet down to as low as a field goal as of this morning.
There is sometimes talk of “pros” vs. “joes” in the betting market. A sizable majority of the public might choose to bet on one side, but the line will move the other way because professional bettors are dropping more money on the other side.