Most people will come around. There will be a few deadenders who will be determined to waste their vote on some 3rd party schlub who has no chance to win, but for the most part beating Obama will carry the day for the vast majority of folks.
The one issue will be how the Palin die hards react when she announces she is not running for President. There is a chance she will continue teasing it out some more by announcing that she isn't running for "the Republican nomination for President in 2012". This would make some of them believe she might run an indie campaign and leave them on the sidelines for many more months.
At the end of the day though, I think most Republicans, conservatives and Tea Party folks want to kick Hussein's carcass out of the White House bad enough to vote for whomever the GOP nominates. My guess is the nominee is likely to be Perry, and I'd bet were are going to see a Perry/Rubio ticket.
FR has turned into a bastion of medocracy. Its been overrun with moderate and liberal republicans.
At the end of the day if true conservatives vote for either of these chumps hope is lost for this country.