At the National Review’s conservative summit on Saturday, I asked Governor Romney ‘s spokesman about the latest story floating around the Internet questioning his candidate’s true conservative bonafides. In this case, it was the disclosure that Mr. Romney had contributed $1,500 to three Democratic candidates in the 1992 election cycle.

Kevin Madden quipped, “You know, there was a time when Ronald Reagan did not work for Republicans.”

It was the first of many references to the 40th president Saturday evening about a man who is in many ways a Reagan reference himself. The former Massachusetts governor parts his hair the way Reagan did, his voice sometimes dips into the Gipper’s slight gravel, and he holds his arms and shoulders loosely near his side. Don’t be surprised if he starts answering questions from reporters, smiling, with the preposition, “well.”

Mr. Romney, unlike Reagan, was never actually a Democrat. He once, however, was an independent. For the purposes of Republican politics, Mr. Romney embraced policies anathema to the party’s core convictions. In 1992, he voted for Paul Tsongas in the presidential primaries. In a 1994 debate against Senator Kennedy, when accused of embracing the former president’s tax cuts, he said, “I was an independent during the time of Reagan Bush, I’m not going to return to Reagan Bush.”

Jennifer Rubin in the Weekly Standard this week uncovers Mr. Romney’s pledges to pro-abortion groups during his 2002 campaign for governor. At the end of a questionnaire from the National Abortion Rights Action League, he wrote, “I respect and will protect a woman’s right to choose. This choice is a deeply personal one. Women should be free to choose based on their own beliefs, not mine and not the government’s.”

Politicians have a right to change their minds. Mr. Romney has staked out some conservative ground, having done what he could to prevent homosexuals from marrying after his state’s Supreme Court decreed that same-sex marriage was a civil right. He also staved off an attempt by his state’s Legislature to impose retroactive capital gains taxes. When former Iranian president, Mohammed Khatami, was invited to speak at Harvard, the governor denied him state troopers for his security detail.

All of these things will accrue him credit with America’s Republicans. How sincere the base will judge his conversion on abortion, however, depends on how well he explains it. So here it is, because you will hear this story a thousand times in the primary season.

On the stump Mr. Romney starts off with a joke: “On abortion I was not always a Ronald Reagan conservative. Neither was Ronald Reagan.” Then he proceeds to explain that he changed his views after talking to the head of stem cell research at Harvard University. He was exploring the issue because his Legislature was working up a bill to define when life began. The doctor then told the governor that “there was no moral issue” that pertained to his embryo farm because the embryos were killed after 14 days.

Mr. Romney, thunderstruck, turned to his chief of staff and vowed from that day on to be pro-life. “We have so cheapened the value and sanctity of human life in our society for someone to think there is not a moral issue because we kill human embryos at 14 days,” he tells the crowd.

This conversion is Reaganesque. When Reagan was governor of California, he was pro-choice. But when he ran for president in 1980, Reagan declared that as the science changed, proving the viability of life before birth, his views changed. Mr. Romney is also making an appeal to science before faith by asserting that the embryos farmed at Harvard are living.

At the same time, Reagan never told his state’s voters, as Mr. Romney has, that he favored legal abortions since a close relative of his died of an illegal one. Mr. Romney also poured it on a bit thick Saturday during the question and answer session. He said at one point that he had not, until a few years ago, even thought about the question of when life began.

So for social conservatives, the jury on Mr. Romney is still out. The chairman of the American Conservative Union, David Keene, yesterday said that the former governor at times appears too slick. “Is that evidence of sincere conversion or change in views?” Mr. Keene asked. “Or is it evidence of hypocritical pandering? Or is it evidence that he does not have views? Those are three options, and I don’t know the answer.”

The president of Americans for Tax Reform, Grover Norquist, on the other hand, is not worried. “A successful conservative movement accepts converts one direction, one time, cheerfully,” he said, noting that Mr. Romney’s adoption of the social conservative issue set is an example of one direction, one time conversion.

As for me, I like the governor’s old views on abortion and social issues. I also like Mr. Romney’s current views on the war and how he warns against giving into the alleged grievances of our Islamist enemies. I just hope he doesn’t change his mind about foreign policy after meeting with some Harvard doctor of international relations.