McCain Runs From Bush -- but Not Too Far

Since then, the GOP has lost three House seats in special elections -- an ominous sign for the party and its probable nominee.

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"They've got to get some separation from the president," Rep. Tom Davis, R-Va., said of Republicans running in 2008. "The president is the face of the party. He is absolutely radioactive, at this point. And they're seen as just in lock step with him on everything. … I'm talking about congressional Republicans at this point and McCain, to a certain extent."

Unpopular as the president is overall, his approval rating remains high among Republicans. He is still an effective fundraiser and may be deployed to campaign for McCain among select, conservative audiences.

But voters won't likely see Bush and McCain together in public on the campaign trail. That might be a dream team photo op -- for the Democrats.