It appears just the opposite is happening. Crist and Meek are effectively splitting the Democratic vote and Rubio is losing a much smaller percentage (15-20%) of Republicans to Crist. Crist is facing a no-win situation. If he goes even harder for Dem votes, he risks losing the 15-25% support he is currently getting from Republicans and he might also cost himself support among indies as well.
Rubio 43%Crust retires from politics, writes a book nobody buys, starts selling real estate in the Everglades...
Meek 39%
Crust 17%
Hanging chad 1%