If Crist runs, he wins. Simple as that. If not, we're looking at a very competitive race.
I said it to another thread. The Democrats should be rooting for Charlie Crist to enter the race.
Sure, he will probably scare away every respectable opponent, Republican and Democrat, and will be the heavy favorite to win.
But at the same time, there will be an opening for Alex Sink to win the governorship. And with the 2010 census and subsequent redistricting just around the corner, I bet the Democrats would happily trade a senate seat for having a chance to reverse the republican imposed gerrymandering. Now that Florida is projected to gain two more seats, it is even more urgent.