TAMPA, Fla. -- The problem with Washington is that it is not using the freshest ingredients, according to one former Republican presidential hopeful.

Herman Cain, the former CEO of Godfather's Pizza who led the GOP primary for a time last fall, fired up a crowd of Tea Party supporters at megachurch here Sunday night at the TeaParty.net Unity rally.  And though none of the speakers gathered here will appear on stage during the Republican National Convention, the rally was meant to be a show of force of their impact on this year's election.

"The way you make the best pizza, like Godfather's Pizza, you use the best ingredients," Cain told reporters after his speech. "You use the best beef, the best pepperoni, the best sausage, the best cheeses, the best dough. In the United States of America, we don't have the best ingredients in Washington D.C."

Robyn Beck / AFP - Getty Images

Former candidate for the Republican nomination in the 2012 US presidential election Herman Caine speaks at a Tea Party Unity Rally at The River at Tampa Bay Church in Tampa, Florida, on August 26, 2012 ahead of the Republican National Convention.

Though the event was held at The River Church, the focus was more so on the importance of Tea Party principles than it was on faith.

Minnesota Rep. Michelle Bachmann, who also ran for president, addressed the more than 500 attendees as did conservative radio host Neal Boortz and Rep. Jason Chaffetz, who spoke on behalf of Mitt Romney.

"We are not an unwanted, second class political party.  We are the conscious of the United States Constitution, and we don't apologize for that," Bachmann told the enthusiastic crowd.  She said the tea party influence can be seen in the Republican party's draft platform, which includes a call to audit the Federal Reserve and strictly prohibiting abortion.

But it was Cain who was the headliner and who received the loudest reception.  Despite leading the Republican presidential primary for much of October, the former businessman said he is not disappointed about his absence from the the list of speakers at the RNC.  He told the crowd that his goals have not changed since his run for office, stating, “I’m still on a mission to defeat Barack Obama!”

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Cain was quick to voice his praise for Romney's choice of Wisconsin Rep. Paul Ryan as his running mate. "He didn't make the safe choice, he made the bold choice," Cain said after his speech.

He also defended the presumptive GOP nominee over a recent joke he made in his home state of Michigan, where, touting his hometown roots, Romney quipped, "No one's ever asked to see my birth certificate."

"I just think it was a good joke.  I dont think he was trying to bring up the birther issue.  hey, cut the man some slack, he's running for president.  he can crack a joke every once in a while," Cain said.