Mitt Romney and his allies opened a multi-pronged attack Tuesday on President Obama’s stewardship of taxpayer dollars, as Romney won the Texas primary and clinched the Republican presidential nomination.

Romney garnered at least 88 delegates in the Texas primary, bringing his total past the 1,144 delegates needed to win the nomination, according to an Associated Press count.

But the candidate’s historic feat — he is the first Mormon to win a major party’s nomination — and his economic message were overshadowed by Donald Trump, who was helping Romney raise money at the Trump International Hotel in Las Vegas.

The provocative real estate magnate used the spotlight to promote his long-debunked contention that Obama was born in a foreign country. Romney aides admitted that this was an unhelpful distraction. At a moment when they wanted to put the president on the defensive, it was Romney who found himself in that position, leaving it to his aides to assert that he disagrees with Trump — while Obama’s aides said his refusal to publicly condemn his surrogate showed poor moral leadership.

With the general-election campaign underway, the Obama and Romney campaigns are working to negatively define each other for the independent voters who will decide the race in battleground states.

Romney, who thinks the economy will remain voters’ top concern, is trying to brand Obama as unfit at the helm. He says that, in contrast to himself, Obama lacks the private-sector experience to revive the economy — going so far as to argue that the president doesn’t understand how the nation’s “free economy” works.

Obama, meanwhile, is trying to make what Romney sells as a chief advantage — his 25 years as a businessman — a liability by highlighting his tenure as a founder and chief executive of Bain Capital, a corporate-buyout and venture-capital firm. Obama and his allies are pointing to companies that Bain took over, that ended up in bankruptcy and making massive layoffs.

Romney’s fresh offensive is designed in part to neutralize Obama’s critique. “This isn’t the first time he’s attacked free enterprise,” Romney campaign spokeswoman Andrea Saul said of the president’s Bain comments. “He’s been doing it in word and deed the whole time he’s been president.”

‘Good for them. Bad for us.’

The Romney effort began Tuesday morning with a Web video highlighting the Obama administration’s loan-guarantee investments in four renewable-energy firms — Solyndra, First Solar, Ecotality and Sun Power — that lost money and laid off workers.

“Obama is giving taxpayer money to big donors,” the video’s narrator says, “and then watching them lose it. Good for them. Bad for us.”

American Crossroads, a Romney-allied super PAC, made a more direct link between some of those energy companies and the Bain Capital attacks, accusing the president of engaging in “public equity” by lending taxpayer dollars to corporations that eventually cut jobs.

“Failed investment strategies,” says an online video that the PAC leased Tuesday. “Jobs eliminated. Billions lost. Public equity President Obama: Playing Wall Street games with our money.”

The White House, in response, defended the loan-guarantee program and argued that it was different from private equity because it was for the public good.

“Look, there is the difference in . . . your overall view of what your responsibilities are as president and what your view of the economic future is,” White House press secretary Jay Carney told reporters Tuesday.

“And the president believes, as he’s made clear, that a president’s responsibility is not just to those who win, but . . . for example, in a company where there have been layoffs or a company that’s gone bankrupt, that we have to make sure that those folks have the means to find other employment.”

Obama campaign spokesman Ben LaBolt sought to return to the attack against Romney and his time as “a corporate buyout specialist.”

“He has claimed time and again that his goal was job creation, but the workers who lost their jobs when he profited off of bankrupting companies and outsourcing know that wasn’t the case,” LaBolt said in a statement.

On Tuesday, Romney began what aides described as a series of symbolic campaign stops across the West orchestrated to amplify the new message from his Boston headquarters.

At his first stop, in a remote Colorado coal-mining town, there seemed to be a disconnect between Romney’s more generic economic message and the sharp shots his aides were firing.

“Some of these liberals say they like a strong economy, but then they act like they don’t like business, and the economy is nothing but the collection of all of our businesses together,” Romney said. “I want our government to support small business, middle-size business, big business. I want jobs. I want government that is an ally of business, not an enemy of business,” he added.

Rallying about 1,000 people in Craig, Colo., where supporters wore baseball caps that said “Coal=Jobs” and workers at a nearby mine were given the morning off to hear him speak, Romney said Obama had failed with the 2009 stimulus and other measures to deliver on his promises of a new “green economy.”

“He said he was going to create some 5 million green-energy jobs,” Romney said. “Have you seen those around here anywhere?”

Yet he was confronted with signs of economic renewal. Local officials told reporters that Craig has rebounded from the recession and that the energy industry there is strong.

“Now [Obama’s] campaign these days is trying to find a twig to hang onto, some little excuse that they grab and say, ‘Well, things are getting a little better, aren’t they?’ ” Romney said.

“And the answer is, yes, things are getting a little better in a lot of places in this country. But it’s not thanks to his policies. It’s in spite of his policies.”

Overshadowed by Trump

A few hours later, when Romney landed in Las Vegas for his next campaign stop, he was overshadowed by Trump — literally. As Romney stepped off his plane, his backdrop was Trump’s black Boeing 757, bearing the ­tycoon’s name in bold letters.

The real estate executive and reality TV star spent the day trumpeting the discredited “birther” movement, saying in a series of TV interviews that he doubts Obama’s birth certificate stating he was born in Hawaii.

Romney did not personally condemn Trump, which prompted Stephanie Cutter, Obama’s deputy campaign manager, to issue a tough statement. Calling Trump a “charlatan,” she said that Romney’s “refusal to condemn his disgraceful conspiracy theories demonstrates his complete lack of moral leadership.”

In introducing Romney at the evening fundraiser, Trump made no mention of the birther controversy, instead saying that the candidate “will carry us to victory.”

Romney, with Trump at his side at Trump’s namesake hotel, acknowledged the milestone he reached Tuesday night.

“I know the road to 1,144 was long and hard, but I also know the road to 11/06, Nov. 6, is also going to be long, it’s going to be hard,” he said of the fall election. “It’s going to be worth it because we’re going to take back the White House and get America right.”

Rucker reported from Washington.