WASHINGTON (Reuters) - Seeking to put to rest questions on whether Barack Obama was a straight shooter when he claimed he went skeet shooting "all the time," the White House on Saturday offered proof: a photo of the president blasting away at clay targets.

Obama drew skepticism when he made the assertion in a recent interview with the New Republic magazine, an attempt to show sympathy for hunters even as he pushes for tighter gun controls after the Newtown school shooting massacre in December.

Obama's aides were in the awkward position of standing by his comments while resisting reporters' demands for proof that he was indeed a regular on the shooting range at the presidential retreat in the Maryland mountains.

The White House finally weighed in on Saturday with a photo of Obama skeet shooting at Camp David last August 4.

"For all the ‘skeeters'," Obama senior adviser Dan Pfeiffer said in a Twitter message linked to the photo, which showed the president - wearing sunglasses, jeans and noise mufflers on his ears - firing a rifle with smoke spraying from the barrel.

It was unclear, however, whether a single photo would satisfy skeptics about his claim that he and his guests frequently shoot clay pigeons at Camp David.

Obama, in the New Republic interview, was asked if he had ever fired a gun.

"Yes, in fact, up at Camp David, we do skeet shooting all the time," Obama said.

"The whole family?" he was asked.

"Not the girls, but oftentimes guests of mine go up there. And I have a profound respect for the traditions of hunting that trace back in this country for generations. And I think those who dismiss that out of hand make a big mistake."

Conservative critics immediately questioned the Democratic president's assertion, and talk show comedians had a field day with the idea that he had taken up shooting as a hobby.

U.S. Representative Marsha Blackburn, a Tennessee Republican, even challenged Obama to a skeet-shooting contest.

Obama's comment was widely seen as an attempt to reach out to gun owners to ease their concerns about his legislative proposals, the biggest gun control push in decades. He will travel to Minnesota on Monday to speak on gun control.

(Reporting By Matt Spetalnick; Editing by Vicki Allen)