In Vegas, Romney claims the nomination, but the focus is on Trump

— -- LAS VEGAS—Less than an hour after he officially clinched the 1,144 delegates needed to claim the Republican presidential nomination, Mitt Romney celebrated his win by mingling with high-dollar GOP donors at a $2 million fundraiser here.

But it was hardly a victory lap for Romney. On a day that normally would have meant lots of free media for Romney's campaign, the Republican contender's message was instead overshadowed by one of the hosts of Tuesday's event, Donald Trump, whose renewed interest in casting doubt on President Obama's American birthright has dominated the news cycle in recent days.

Of course, you wouldn't have known that from Tuesday's fundraiser, where both men were careful to stay away from the birther controversy.

Introducing the Republican nominee, Trump avoided the hot button subject, instead talking up Romney's ability to rebuild the economy and strengthen the nation's standing around the world, especially on trade issues.

"He's going to turn this country around. He's going to create jobs like you haven't seen for many, many years," Trump declared. "We were a great country. Soon we won't be a great country at all... Mitt Romney will make us a great country again."

When Romney took the stage, he politely thanked his host—giving Trump props for "twisting the arms" necessary to make the financial event happen.

"I appreciate your help," Romney said.

But the Republican nominee quickly turned the focus to the path ahead, warning supporters that the path to November wouldn't be easy.

"I know the road to 1,144 was long and hard, but I also know that the road to 11/06, November 6, is also going to be long," Romney said. "It's going to be hard and it's going to be worth it because we're going to take back the White House and get America right again."

Among those in the crowd in Vegas: Former House Speaker Newt Gingrich, who joined his former rival on the trail for the first time since dropping his own bid for the Republican nomination last month.

While Gingrich didn't speak at the fundraiser, he talked to reporters ahead of the event, defending Romney's muted reaction to Trump's birther conspiracies.

"Gov. Romney is not distracted, the Republican Party is not distracted. We believe this is an American-born, job-killing president," Gingrich told reporters, per the Los Angeles Times. "Other people may believe that he was born somewhere else and still kills jobs, but that's an argument over background. The key fact is for any American worried about the economy, Obama is a job-killing president."