Will Rick Perry’s past come back to haunt him?

If Texas Governor Rick Perry jumps into the 2012 presidential race, as so many now expect, his past could come back to haunt him.

A group of New Hampshire Tea Party activists are already circulating information that highlights aspects of Perry’s political record that could prove highly embarrassing to those looking to promote him as a “red meat” conservative alternative to GOP frontrunner Mitt Romney.

It’s still not widely known, but Rick Perry, like Ronald Reagan, was once a Democrat. And unlike Michele Bachman, who became a Republican in 1980 and voted for Reagan, Perry was a Democrat — albeit a conservative one — right through Reagan’s first and second terms. In fact, in 1988, he backed Al Gore’s presidential candidacy (though at the time, Gore was known as a Southern conservative).

Perry became a Republican in 1989, but he has continued to frequently back moderates for elective office. In 2008, he was a huge supporter of former New York City Mayor Rudy Giuliani’s presidential bid, despite Giuliani’s pro-abortion stance.

Perry has long been a moderate on immigration issues. He supports securing the border in order to prevent drug smugglers and illegal immigrants from crossing into the U.S., but he has also supported giving college tuition breaks to illegal immigrants and has opposed the construction of the U.S.-Mexico border fence as well as controversial immigration laws like Arizona’s SB 1070, which gives Arizona police the authority to stop and question residents about their legal statuses.

Even moderates like John McCain support the border fence and SB 1070. Perry, however, favors expanded use of ground sensors and other modern technology in lieu of a fence and thinks that Arizona-style enforcement laws are too difficult to implement and could divert resources from more pressing crime-fighting efforts.

Perry is a staunch opponent of Obamacare, but he has one Romney-like skeleton in his closet. In 2007, he signed an executive order mandating that teenage girls in Texas get vaccinated against human papillomavirus, which causes cervical cancer. But the vaccine is largely untested, and even the FDA has ruled that it could have harmful effects and shouldn’t be approved for public use until more tests are conducted.

Virtually the entire Texas Legislature rebelled against Perry on the issue, and it remains one of the reasons that Perry’s popularity has sagged. In one recent state poll, just 4% of Texans said that Perry should run for president.

Perry, with characteristic bravado, brushes off his Texas critics, noting that “no prophet is ever popular in his own hometown.” And his advisors say that despite his past support for tax increases as a Democrat, he’s since established a 20-year record as a fiscal conservative and has signed some of the largest tax cuts in Texas history.

But Perry has got to be worried. Michele Bachmann is already surging nationally and emerging as the Tea Party alternative to Mitt Romney. She’ll need to jealously guard her political ground if Perry jumps into the race and attempts to claim the same mantle.

But even if Bachmann decides to tread lightly, don’t expect New Hampshire Tea Partiers to follow suit. They’re liable to portray Perry as a Johnnie-come-lately to the conservative cause, or even a closet RINO whose support for mandated vaccinations suggests latent big-government tendencies.

Does that sound preposterous? In the grand scheme of things, perhaps, but in hotly contested primary races in states like New Hampshire, even tempests in a teapot have a way of boiling over.

Stewart J. Lawrence is a Washington, D.C.-based public policy analyst who writes frequently on immigration and Latino affairs. He is also founder and managing director of Puentes & Associates, Inc., a bilingual survey research and communications firm.