Ron Paul’s underdog presidential campaign is out with a new ad in Iowa and New Hampshire that hits Rick Perry for his former life as a Democrat, focusing on the Texas governor’s support for Al Gore in the 1988 presidential race.

“Al Gore found a cheerleader in Texas named Rick Perry,” the ad says. “Rick Perry helped lead the Al Gore campaign to undo the Reagan Revolution, fighting to elect Al Gore President of the United States.”

The ad is the first high-profile example of an attack that will likely be revisited upon the Texas governor in the weeks and months ahead, as Perry’s opponents attempt to call into question the Republican’s true conservatism.

But the charge deserves some context, too. While perhaps not as damaging as it would appear on the surface, the Gore connection is fair game going forward and could pay dividends for Perry’s opponents if it leads voters to question Perry’s political authenticity.

First and foremost, it’s imperative to note that back in the 1980s, the vast majority of whites in the South were Democrats; Texas’s congressional delegation, for example, included 19 Democrats out of 27 House districts at the end of that decade. In that way, Perry’s decision to become a Republican before running for state Agriculture Commissioner in 1990 wasn’t all that unusual. He actually followed in the footsteps of another big-name Texas politician – former senator Phil Gramm – and many other high-profile Southern Republicans, not to mention Reagan himself.

Second, while today we know Gore as the environmental crusader and East Coast liberal folk hero, that wasn’t quite the image he had cultivated in 1988. Back then as a Tennessee senator, Gore was a more middle-of-the-road Southern Democrat, including on issues like abortion rights, guns and foreign policy. He often called himself a “raging moderate.”

Perry tried to play up Gore’s more conservative side when asked last week about the endorsement in an interview with Fox News’s Sean Hannity.

“Al Gore appeared to be the most conservative — a strong Strategic Defense Initiative guy — and frankly, we thought that he would be the most conservative Democrat,” Perry said. “You know, we were wrong.”

In fact, Perry has repeatedly pointed to Gore’s support for the Strategic Defense Initiative, which is also known as Star Wars. But as ABC’s Michael Falcone points out, before his presidential campaign, Gore had actually disowned his support of the program.

As this example shows, mining Gore’s record for more conservative positions is relatively difficult because Gore wasn’t terribly conservative back then. Sure, Gore was more moderate than he is today, but he was still someone with a foot in both the more elite East Coast Democratic establishment as well as in more rural Southern Democratic circles.

The Almanac of American Politics — a.k.a. the Fix’s Bible — in 1990 described Gore as a “generally liberal” senator who was “closer to traditional Demcoratic big government views than other Democrats, notably Michael Dukakis” while more hawkish than his party on foreign policy issues.

Not exactly a conservative South Democrat.

What’s more, by endorsing Gore and getting involved at all, Perry was actively aligning himself with the national Democratic Party and its potential nominee. These days, conservative or middle-of-the-road Democrats will often distance themselves from President Obama for fear of being too closely attached.

A great example of that is Gramm. Even back when he was a Democrat, Gramm surveyed his district and decided that supporting Jimmy Carter for president would be too risky, according to a recent book on the shift towards the Republican Party in the South.

The fact is that any time a candidate decides to endorse another candidate, they are, at least a little bit, putting their career on the line. For years and even decades, they can be tied to that endorsed candidate, and a lot can change in that span – as we’re finding out with Perry and Gore.

Lastly, it’s worth noting that very few politicians have clear and consistent positions throughout their career. In fact, even the candidate running the first Perry-Gore ad has his problems.

Paul, as is often noted, left the Republican Party in the very same 1988 campaign to run as the Libertarian Party presidential candidate. And while Paul plays up his support for Reagan in the ad, he has repeatedly referred to Reagan as a “failure,” even recently — particularly when it comes to growing the size of government.

When it comes to career politicians, these kinds of shifts will often occur over time. The question for a lot of people will be whether the shifts are genuine or betray a type of political expediency that questions their trustworthiness.

Perry is dealing with this attack on several fronts — including recent reports that he offered some level of support for then-First Lady Hillary Rodham Clinton’s health care proposal in 1993 and that he supported the Troubled Asset Relief Program (TARP) bailout as head of the Republican Governors Association in 2008.

To some extent, Perry will have to prove he has always been the conservative hero he’s supposed to be today. And the Gore endorsement, while it may not kill him, won’t help.

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