Poor Crist's numbers are dropping (though we must always take Rasmussen's reactionary-leaning polls with a grain of salt).
The irony of it is, had Crist run for re-election as governor, he would likely have faced only token opposition (Sink almost certainly would either have run for re-election as CFO or gone after the Senate seat herself).
It looks increasingly likely that the blowback from Crist's decision to forgo a second term as governor could include a loss in the Republican primary, the ouster of his good friend Jim Greer from the chairmanship of the Florida Republican Party, and a Democrat in the governor's mansion (giving the Democrats an equal seat at the bargaining table during redistricting - thereby threatening the GOP's gerrymandered control of the legislature by 2014).
Oh, and Crist's 2016 presidential ambitions? He can just forget about it.