Bush again alone in the lead:
Bush 16.8
Rubio 16.3
Paul 11.6
Christie 10.0
Cruz 6.2
Walker 6.0
Ryan 5.5
Huckabee 3.6
Four years ago today on Intrade:
Romney 30.0
Palin 20.0
Thune 12.5
Gingrich 10.9
Pawlenty 10.4
Daniels 8.5
Huckabee 6.9
Pence 5.0
In that case, only 3 of the people in the top 8 ended up running (Romney, Gingrich, Pawlenty). They were 1st, 4th, and 5th respectively on Intrade. If history were to repeat itself this time around, we'd see Bush, Christie, and Cruz run, but none of Rubio, Paul, Walker, Ryan, or Huckabee.
I don't think there's any foreseeable scenario under which Rand Paul opts not to run.
