WEST PALM BEACH, Fla. -- Businessman Herman Cain threw his support to Republican presidential contender Newt Gingrich late Saturday.

The move by the former GOP candidate and tea-party favorite comes three days before the Florida primary, at a moment when Gingrich is badly in need of something to rekindle the momentum he gained in the wake of his South Carolina primary victory.

Since then, polls have shown that he is losing ground against former Massachusetts governor Mitt Romney in this state, even as Gingrich has gained a lead in national surveys.

“I had it in my heart and mind a long time,” Cain said of his endorsement, appearing with Gingrich at a Republican fundraiser. “Speaker Gingrich is a patriot. Speaker Gingrich is not afraid of bold ideas.”

Gingrich joked, “I had no idea it would be this interesting an evening.”

Cain is the latest in a series of popular conservative figures to back the former House speaker, while much of the GOP establishment is marshaling against him. Among Gingrich’s other recent supporters are former Alaska governor Sarah Palin; his onetime presidential rival, Texas Gov. Rick Perry; and former senator Fred Thompson (Tenn.)

Cain’s own presidential bid ended in November amid allegations of sexual harassment and marital infidelity. But the former Godfather’s Pizza executive had ridden a wave of popularity prior to that scandal with his signature “9-9-9” tax reform plan and a charismatic and confident conservatism that found broad appeal among tea party-friendly activists.

At the peak of his popularity, Cain was attracting thousands of supporters to his rallies and earning cheers and applause in his folksy debate performances.

He remains popular today among grassroots conservatives. He demonstrated particular popularity in Florida, where he earned a surprising win of a straw poll last summer -- and launched his dramatic, if short-lived, rise to the top of the field.

Since he left the race, Cain has been coy about whom he would endorse; last week, he said he was planning to endorse “We The People.”

Although Gingrich needs any boost he can get in Florida, the timing of the endorsement was odd -- too late to make the evening television news casts, and sandwiched before the expected release of a new NBC/Marist poll widely expected to show a widening lead for Romney.

Gingrich said he hopes Cain will co-chair a commission to lead the policy discussion on the economy and taxes. He compared the idea to his request that Perry lead a commission on the 10th Amendment, which he proposed when Perry endorsed him in advance of last weekend’s South Carolina primary.

“I realize that as a co-chair of a commission like that, there would be a little thing called 9-9-9 that would be brought in and put on the table. So I fully expect that,” Gingrich said.

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