Florida Gov. Charlie Crist (I) faced a barrage of questions Tuesday night over his decision earlier this year to bolt the Republican Party to run for the Senate as an Independent.

In the sixth and final face-off between Crist, Republican Marco Rubio and Rep. Kendrick Meek (D-Fla.) Tuesday, Crist repeatedly defended his decision in the face of pointed questioning from debate moderator David Gregory.

At one point, Gregory held up a copy of the Republican Party platform, asking Crist how voters could trust a politician who is now shunning policy positions he strongly advocated in the recent past.

The governor described his switch as "a heartfelt change of views" and said thanks to his newfound independence from the GOP, "I'm liberated and I'm free."

Crist repeated his contention that the GOP has moved too far to the right and said he was no longer comfortable in his own party.

The governor's party switch came this past April at a time when it was increasingly clear that he would lose the Republican nomination to Marco Rubio.

Tuesday was the governor's last chance for a closing argument in a race that hasn't appeared competitive in more than a month, but Crist spent most of the debate on the defensive. 

The latest CNN/Time poll in Florida's three-way race gives Rubio a 14-point edge in the contest. Rubio leads with 46 percent of the vote to 32 percent for Crist and 20 for Meek.