Clinton is scheduled to appear at rallies with the congressman in Delray Beach, Davie and Miami on Aug. 16.
Meek was considered the favorite to win the Democratic nomination, but is now trailing billionaire Jeff Greene, who announced his candidacy on the last day to qualify for the ballot.
Greene has spent more than $6 million of his money on the campaign.
In a recent Quinnipiac University poll, Greene led Meek 33 to 23 percent.
Meek began a 10-door bus tour to energize his campaign earlier this week.