"It was a mistake, and I'm sorry," Pawlenty said. "You're going to have a few clunkers in your record."
Time was, so-called cap-and-trade regimes were the latest in conservative environmental policymaking. The idea was that the market would create incentives for utilities and industries to limit emission of the gases that contribute to climate change, and encourage new technology and greener fuels. That was supposed to be better than the traditional approach, with bureaucrats in Washington and state capitals monitoring each smokestack.
But conservative elite opinion shifted, most markedly in 2009 as the recession deepened, President Obama took office, and the House considered his cap-and-trade proposal. Suddenly, it was a "job-killing energy tax" that would put the United States at a disadvantage with international competitors - such as China - that have no carbon controls. Conservatives also raised doubts about whether human activity was the cause of warming trends.
Gingrich, the former House speaker, illustrates the change well. Four years ago, he was in an environmental group's TV ad, sitting on a couch with Democratic then-Speaker Nancy Pelosi to urge action on climate change. And, in a February 2007 interview with PBS, Gingrich said: "I think if you have mandatory carbon caps combined with a trading system, much like we did with sulfur, and if you have a tax-incentive program for investing in the solutions, that there's a package there that's very, very good."
One recent evening, in a Manchester, N.H., living room, presidential candidate Gingrich was in tune with the times. He told the conservative activists gathered in the room that "climate change is the newest excuse" for left-wing intellectuals "to take control of lives."
In his first few weeks of campaigning, Gingrich also had to shed a second great apostasy, after he acknowledged on NBC's Meet the Press that he supported requiring individuals to buy health insurance, a central part of Obama's national health-care overhaul. Gingrich said it was a matter of "personal responsibility" - a conservative principle - to take care of yourself and not push your health costs on fellow citizens. He was pummeled for it, and now says that Obama's individual mandate is an "unconstitutional" infringement on liberty.
But conservative Republicans developed the concept in the 1990s, when Gingrich was in power, seeing the requirement as a way to lower health costs and broaden coverage by using the market. It was a counter to the government-centered system championed by then-first lady Hillary Rodham Clinton.
As governor of Massachusetts, Romney included the individual mandate in his health-care program, which was used as a model by the experts who drew up Obama's plan - a fact that now threatens Romney's candidacy.
Huntsman, who was governor of Utah and most recently Obama's ambassador to China, also has found himself crosswise with his record. He joined a consortium of Western states in a cap-and-trade program in early 2008, but has wasted no time in disavowing that move now.
"Circumstances change," Huntsman said recently on ABC's Good Morning America.
Well, the economy has tanked in the last three years, though presumably whatever was happening with the climate that made Huntsman think cap-and-trade was a good idea is still relevant, since climate trends are long-term.
What has really changed is the ideological center of gravity in the Republican Party, and the understanding of what it means to be conservative.
It used to be considered desirable for the government, in concert with free-market principles, to work to achieve social goods such as increased access to health care or clean air. In the tea-party era, though, government is seen as good only for getting out of the way.
Contact politics writer Thomas Fitzgerald at 215-854-2718 or firstname.lastname@example.org. Read his blog, The Big Tent, at www.philly.com/bigtent.