Published: Apr 28, 2010 10:35 PM EDT

UPDATE:  Crist announces run as independent candidate

TALLAHASSEE, Fla. - A close confidante of Florida Gov. Charlie Crist says the Republican likely will bolt the party and seek election to the U.S. Senate as an independent. Crist will announce his plans at 5 p.m. Thursday in his hometown of St. Petersburg.

The confidante, who spoke on condition of anonymity because the announcement has not been made, cautioned that Crist can be unpredictable. The announcement will end weeks of speculation about whether Crist will abandon the GOP after falling far behind former House Speaker Marco Rubio in polls.

Crist has openly considered running without party affiliation. Top Republicans have encouraged him to stay in the primary or drop out rather than risking a split vote that could benefit likely Democratic nominee U.S. Rep. Kendrick Meek.

Crist did not return calls for comment Wednesday.

Notably, it has also been announced that Congressman Connie Mack will run for re-election.

Related:

Crist announces run as independent candidate

Marco Rubio comments on 2010 U.S. senate election