Politically astute Republicans, including many social conservatives, see Mitt Romney as the strongest candidate to beat President Obama in November. The former Massachusetts governor may not be their kind of Republican, but any Republican would be better than Obama, in their opinion.

The view that Romney would be Obama's most formidable foe is accurate -- but only as of Monday, when former Utah Gov. Jon Huntsman dropped out of the race. At a news conference in Myrtle Beach, S.C., Huntsman threw his support behind Romney, who is currently engaged in a South Carolina primary death match against former House Speaker Newt Gingrich.

In a general election, the above thinking goes, Romney would appeal to many unaffiliated voters, now 40 percent of the electorate. But Huntsman could have appealed to them also, plus picked up some independent-minded Democrats. Sadly, his kind of moderation and refusal to pander has gone nowhere in the hyper-partisan steam room of Republican caucus and primary politics.

The jig was clearly up for Huntsman after he finished third in the New Hampshire primary, after Romney and Ron Paul. Huntsman had put all his chips on the Granite State. He said the right socially moderate and fiscally conservative things. He respected the local demand for close encounters with candidates. Going from town hall to high school gym, he practiced retail politics at the mom-and-pop level.

Had a broader national electorate been given the chance to judge, the outcome could have been far different. Huntsman ran a grown-up campaign. His emphasis was on what would be good for the country, rather than smiting The Enemy, as construed by the right wing. He was even nice to fellow Republicans.

Thus, he had to defend his decision to serve as ambassador to China. In one of Romney's low debating moments, he said to Huntsman, "I'm sorry, governor. You were, the last two years, implementing the policies of this administration in China." Whether anything was wrong with those policies stood entirely beside the point.

"I believe in my country," Huntsman would reply to such accusations, "and he was president of my country." Having been recently re-elected with 80 percent of the vote in conservative Utah, he must have found it strange having to justify his Republican bona fides.

Huntsman refused to indulge Republicans hostile to modern science. "To be clear, I believe in evolution and trust scientists on global warming," he tweeted. "Call me crazy."

The candidate was asked on ABC to justify that statement from a political horse race standpoint. He said that the minute Republicans become the anti-science party, "we lose a whole lot of people who would otherwise allow us to win the election in 2012."

Above all, Huntsman was a class act in a low-class campaign. In withdrawing from the fray, he lamented, "This race has degenerated into an onslaught of negative and personal attacks not worthy of the American people and not worthy of this critical time in our nation's history." Indeed, the Republicans are trashing one another with a vigor that makes the opposing punditry redundant.

Huntsman wouldn't sign silly pledges. He wouldn't attend Donald Trump debates. He wouldn't question Obama's love of America.

Huntsman may leave the race with few supporters to pass on to Romney, but he departs with his dignity intact. These days, that's saying something.