President Obama jokingly downplayed the possibility that his ambassador to China might look to challenge him as the Republican presidential candidate in 2012. 

Obama said that Jon Huntsman, the former Republican governor of Utah, would no doubt run into problems in a GOP primary for having worked for a Democratic president.

"I'm sure the fact that him having worked so well with me will be a great asset in any Republican primary," Obama said at a press conference at the White House with visiting Chinese President Hu Jintao.

Obama praised Huntsman for having done an "outstanding job" in almost two years as ambassador to China. "The fact that he comes from a different party, I think, is a strength, not a weakness, because it indicates the degree to which both he and I believe the partisanship ends at the water's edge, and that we work together to advocate on behalf of our country," the president said. 

He said that he expected Huntsman would be successful in whatever future endeavors he chooses after leaving the administration.

When Obama named Huntsman, a centrist Republican governor who speaks fluent Mandarin, it was widely seen as a move to stifle a potential rival for the White House in 2012. Presidential buzz had surrounded Huntsman until he agreed to serve as ambassador.

But that buzz has reemerged as of late, as Huntsman finishes up the two-year term he'd planned on serving as ambassador. He told The Wall Street Journal earlier this week that he hadn't ruled out running for president in 2012.

If he were to run, Obama's joke highlights the playbook Republican foes for the nomination would look to use against Huntsman: his having worked for Obama, before turning around and running for president on the GOP ticket.