The two positives about Senator McCain is that he is pro-life and pro-defense.
Assuming that both of those are important to his supporters, then they could not go to Giuliani who is a declared anti-lifer. All Republicans (except Paul) claim to be pro-Defense.
Romney’s support of the life issue is political opportunism, and most know that.
Thompson needs to make a statement, though. He needs things to break his way and to get a big positive in the news this week. If he does, then I think McCain’s supporters go his way. Otherwise, they go to the entire group except Giuliani and Paul. (And Tancredo who announces his quitting the campaign today, I think.)
I think that Sen. Thompson has the inside track on this group.
Mr. Thompson has actually taken significant criticism for being viewed as too close in the past to Sen. McCain. I believe that Sen. Thompson endorsed Sen. McCain in 2000, and may have served some semi-official role in the campaign.
Up until their divergence on immigration, little separated the two. Both are moderate conservatives, pro-life, pro-defense, have persuasively positioned themselves as fiscal conservatives (although Sen. McCain used that rhetoric to originally oppose the Bush tax cuts).
I wouldn’t be surprised if many McCain supporters were aware that the two men have been close, and are friends, and will return their appreciation for Sen. Thompson’s past support with their support should it turn out that their candidate is circling the drain.
sitetest
Although, McCain supports federal funding for embryonic stem cell research - Romney and Thompson do not. And McCain fought the President on Patriot Act powers, Gitmo procedures and "torture" definitions - Romney and Thompson did not.