Florida law lets Crist keep his job if he accepts the offer and loses. Democratic insiders say having Crist on the ticket could make it harder for their nominee to win Florida, but Democratic National Committeeman Jon Ausman says a Crist win does not make winning the presidency impossible.

"I also think that the Democratic nominee should pick Governor Ted Strickland of Ohio, also a freshman governor like Governor Crist for exactly the same reason, so that Democrats could carry Ohio's 20 electoral votes," said Ausman. "It's a tradeoff. They can have Governor Crist for Florida, we'll take Governor Strickland for Ohio. We'll win the presidency, then we'll get to keep Governor Crist here doing a fine job for Florida."

The question for McCain is whether Crist will make a difference outside of Florida and whether that matters.

Crist will spend the weekend wiht McCain in Arizona at a Memorial Day BBQ.