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Jon Huntsman began his bid for the Republican nomination asking voters to pick a non-extreme opponent to face President Obama, and he ended it by perhaps asking himself how he could poll behind a comedian in a crucial primary state.

Maybe that's fitting: Huntsman's candidacy was a joke to many conservatives and political observers alike. He consistently trailed the other candidates and was the only one not to get a surge of support as a result of conservative voters' desire for someone other than Mitt Romney.

As the New Hampshire primary approached and Huntsman rose in the polls only slightly, it also became clear that his best chance at the White House might not be for another four (or eight) years. Just as Romney dropped out in 2008 to endorse John McCain, the establishment's choice, Huntsman had an opportunity to do the same, bow out gracefully and serve as Romney's surrogate until Election Day.

In that pattern, Huntsman's  Sunday-night decision to endorse Romney was no surprise. "His name is going to come up next time, undoubtedly," Quin Monson, a political science professor at Brigham Young University who has followed Huntsman's run,  told ABC News last week.

"We entered this race just six months ago with the longest of long shots," Huntsman said in a speech to reporters on Monday in which he made official his decision.

Huntsman took no questions after his speech, and he said the Republican primary "has degenerated into an onslaught of negative and personal attacks not worthy of the American people."

"Cease attacking each other," he said in a message to the candidates.

Huntsman's best showing was in New Hampshire, because he basically spent his entire campaign there, and he earned only third place in the primary. That night, Huntsman called his underwhelming performance a "ticket to ride," but it was clear he wouldn't do well in South Carolina, where he polled in dead last, even behind Stephen Colbert, who isn't on the ballot or running for president ( technically).

The best press that Huntsman, 51, got was half a year before any of the primaries, when he announced in late June that he was going to run. The political news media embraced his effort because he was different, the only moderate besides Romney in a field of candidates who were tacking to the right to win over conservatives and Tea Party members. Yet it was because Huntsman refused to follow them in that direction that he never got traction.

For instance, it didn't help him much among a constituency that suspects a climate-change conspiracy theory when Huntsman announced on Twitter: "I believe in evolution and trust scientists on global warming. Call me crazy." Or when The Boston Globe's left-leaning editorial page endorsed him.

How could a candidate like that win any primary in which conservatives are energized to defeat a president they consider way too liberal? Huntsman even worked for President Obama, as his ambassador to China. For many, his candidacy seemed like a pipe dream. Bill Richardson, a Democrat who similarly was an ambassador, a governor and a presidential candidate, told me at the end of September that Huntsman was "not going anywhere."

The candidate did promise not to fit in the mold. "You'll hear things you won't be hearing from any other campaign," he said in an email to supporters just before he announced that he would run for president. "Our campaign is different. Our ideas are different."

Huntsman himself never wanted to play the expectations game in New Hampshire, despite predicting that he would win the nomination. I followed him out of a news conference in December to ask him where he thought he would finish in the New Hampshire primary, but he would only talk about wanting to beat "market expectations."

Unfortunately for Huntsman, the market's closing bell rang months ago.