Continued from page 1

A Crist veto of a bill to make it easier to fire teachers and to link teacher pay to student test scores this year ingratiated him further with the state’s unions and with many Democrats.

The Gulf of Mexico oil spill also afforded him frequent use of his gubernatorial bully pulpit, at a time when his independent campaign was still being organized.

“He certainly has got a reputation for being able to read public opinion just about better than anybody else,” Ms. MacManus said. “He’s definitely a populist in the true sense of the word, and it shows in his campaigning.”

The governor’s switch to independent status effectively rendered the Republican primary meaningless, meaning that Mr. Rubio - who began his campaign last year with a strongly conservative message - has had to begin courting moderates months earlier than expected in anticipation of the November general election, taking a bit of steam out of his campaign.

Mr. Rubio’s surprisingly quick rise to the top of the polls earlier this year also may have left him little room to win over new supporters.

“A lot of Democrats see a lot of difference between him and Rubio, so [Mr. Crist’s resurgence in the polls] has been a combination of his own personal popularity and this concern by Democrats about what Rubio would look like” in the Senate, Mr. Crew said.

Mr. Meek’s primary win almost certainly would cost Mr. Crist some voters. Whether it would be enough to doom the governor’s chances in November, however, has been debated in political circles for months. Mr. Meek’s primary challenger, billionaire political newcomer Jeff Greene, was seen by many as giving Mr. Crist a better shot at picking off disaffected Democrats in November.

A Meek win “puts [Democrats] in somewhat of a tenuous position,” Mr. Crew said. “They can’t overlook a person who has the kind of Democratic credentials that Meek has. On the other hand, I can’t think that a really hard-eyed Democratic observer would look at this race and say Meek has much of a chance of winning.”