The Broncos reached the showpiece event courtesy of a 26-16 victory over the New England Patriots in last night's AFC championship game.
The game will pit Seattle's league-leading defense against the record-breaking offense of the Broncos, and many bookmakers initially sided with a narrow victory for Seattle.
However, a flurry of betting on the Broncos swayed the odds, making Denver slight favourites to win their first Super Bowl crown since 1998.
"We're just trying to figure out what the market will be and get a feel of where money will go. At this point it doesn't take a lot to move the line," Jay Kornegay, who runs the LVH sports book, told the Associated Press.
The match will be played at the MetLife Stadium in New York and is being forecast as the coldest Super Bowl in history.