He'd do better than Huckabee, if only because I think Huckabee would be more likely to pick an incompetent running mate like Palin.
As for compared to McCain, I think he'd have a shot at doing better, as increased conservative turnout might save Indiana, North Carolina and Iowa for Brownback.
Conversely, Arizona flips without McCain on the ballot, and since I assume Brownback doesn't pick Palin, Alaska might flip as well.
NE-2 goes down to the wire, but the collapsing economy gives Obama the victory.
Senator Barack Obama (D-IL)/Senator Joe Biden (D-DE) 52%
Senator Sam Brownback (R-KS)/Former Senator Bill Frist (R-TN) 46%
