Romney plays Trump card in Las Vegas By Ros Krasny and Sam Youngman LAS VEGAS (Reuters) - Republican presidential front-runner Mitt Romney, struggling to recover from remarks that critics said showed indifference to America's poor, on Thursday won the endorsement of real estate mogul Donald Trump. Trump, also a television celebrity who has said he is worth perhaps as much as $7 billion billions, is himself an on-again/off-again Republican presidential candidate and former member of the party, said he would back Romney in the race for the nomination to oppose President Barack Obama in the November 6 election. "Mitt is tough, he's smart, he's sharp," Trump said at a news conference at his Trump International Hotel in Las Vegas, Romney and his wife, Ann, standing to his right. He's not going to allow bad things to continue to happen in this country we all love. So, Governor Romney, go out and get 'em. You can do it. Trump's support could backfire on Romney, a day after the wealthy former private equity executive gave a clumsy reminder of the challenges he faces winning over voters hit by the economic downturn and convincing them he can relate to their problems. "I'm not concerned about the very poor, we have a safety net there," Romney said Wednesday on CNN, adding, "If it needs repair, I'll fix it." Trump said he got to know the former Massachusetts governor during several recent conversations and was impressed with his tough talk on China and said he was won over by Romney's strong performance campaigning in Florida. Romney lashed out at China again. "We have to have a president who will stand up to cheaters," he said at the endorsement announcement. Trump, who announced he was leaving the party two months ago, seems an unlikely choice for Republican kingmaker. But the casino owner and reality television star is popular in Nevada, and from the Romney team's perspective it is better to have him with them than against them. Nevada's caucuses on Saturday are the next contest in the state-by-state process of choosing a Republican nominee. Romney has won two of the first four states, taking primaries in New Hampshire and Florida by healthy margins. Former House of Representatives Speaker Newt Gingrich won South Carolina's primary, and former U.S. Senator Rick Santorum won Iowa's caucuses by a narrow margin over Romney. Trump, who cultivates an aura of glitz and glamour, estimated last year that his personal net worth could be as high as $7 billion. He was derided as he mulled entering the 2012 presidential race last year for pushing a discredited charge that Obama was not born in the United States. I've had some success in the private sector. Not quite as successful as this guy, but successful nonetheless," Romney said. He praised the hotel, and said, after Trump announced his endorsement: "There are some things you just can't imagine happening in your life. This is one of them. Additional reporting by Edith Honan in New York and Steve Holland and Patricia Zengerle in Washington; editing by Mary Milliken and Cynthia Osterman