You could be right DI, we're all guessing at this point. I would be surprised, though, if the Patriots are favored (IF the matchup actually happens). My shot in the dark guess for the spread is somewhere between Patriots +1 to +2. I base this on two factors: (1) Built in Home field advantage of approx. 3.5 for Denver and (2) the teams being considered about an even matchup if theoretically played at a neutral site.
That bottom line says the Patriots would have to be a 4 point neutral site favorite to overcome the HFA that Denver will be given. I just don't see Vegas saying the Broncos rate 4 points less than the Patriots.
Regarding how the spread will be affected by the amount of action that comes in? Denver's winning streak, the Patriots recent struggles, the pundits heaping praise on PM/the Broncos all week leading up to the game will, imho, cause plenty of action to come in on the Broncos.
The caveats to Denver being favored are any key losses to injury in their divisional game and/or they struggle to win their divisional game while the Patriots steam roll their opponent.