Republican presidential hopeful Jon Huntsman says he'd be open to running as vice president if rival and tea party favorite Michele Bachmann wins the nomination.

The former Utah governor, who was appointed ambassador to China by President Barack Obama, says that every time he's been asked to serve his country he's answered "yes." He resigned his China ambassadorial post earlier this year.

Huntsman told CNN interviewer Piers Morgan on Monday that if asked by the Minnesota congresswoman to run as her vice president he'd "be the first person to sign up, absolutely."

Huntsman tried quickly to backtrack, saying the answer was based on a hypothetical question and that he has no doubt he'll win the Republican nomination.

Meanwhile, a newspaper reported that Republican front-runner Mitt Romney wants to nearly quadruple the size of his $12 million oceanfront mansion in La Jolla, California, a move that could alienate him from less affluent Americans struggling through the economic slump.

In the 2008 presidential race, Republican candidate John McCain was stumped by Democratic nominee Barack Obama in a debate when challenged to state how many houses he owned.

McCain's staff later said that he owned four houses; the AP found that McCain and his family owned eight properties.

The San Diego Union-Tribune reports (http://bit.ly/nIPLz1 ) that the former Massachusetts governor has filed an application to demolish his roughly 3,000-square-foot (279-square-meter), single-story house and replace it with a two-story, 11,000-square-foot (1022-square-meter) residence.

The existing, Spanish-style house was built in 1936, has three bedrooms, 4 1/2 bathrooms, a lap pool and spa.

Romney's proposal, along with the necessary site development permits, must be approved by the city.

Romney's spokesman Ryan Williams declined to comment on the renovation plan.

Huntsman, one of the more moderate Republican candidates, hopes to be his party's challenger to Obama, who has begun a long-range campaign for a second presidential term.

But Huntsman has trailed far behind the top tier of Republican candidates in early polls nationally and in early voting states.

Romney has led the pack for months, but attention has increasingly turned to Texas Gov. Rick Perry, a new entrant in the race.