Published: Oct 01, 2010 3:32 PM EDT
Updated: Oct 01, 2010 12:32 PM EDT

TAMPA, Fla. (AP) - U.S. Senate candidate Kendrick Meek was joined at a campaign stop Thursday by ex-Vice President Al Gore, who urged Democrats to make a clear choice in the contentious, three-way race.

"It's a complicated race, as everybody knows," Gore told some 200 mostly Meek supporters gathered at the Tampa Letter Carrier's Hall.

Meek, a Democrat, was one of two candidates in the race this week who are bringing in political heavy-hitters in an attempt to gain support from voters.

On Friday, 2008 Republican primary contender and possible 2012 presidential candidate Mitt Romney is scheduled to attend a rally for Meek's opponent, Marco Rubio.

Rubio and Meek - who is a Democrat - are in a three-way race for a U.S. Senate seat with Gov. Charlie Crist, who is running as a no-party candidate.

On Thursday, Gore urged Democrats to vote for Meek and not Crist.

"I do not really know where he stands on lots of these important issues," Gore said. "We want somebody to stand up for what he believes and stick to it and fight."

Crist's independent bid for the U.S. Senate is ahead among Democrats and independents but the former Republican is getting crushed among GOP voters and that has left him well behind overall, a poll released Thursday showed.