BLUFFTON, S.C. (CBSNewYork/AP) — If you’re looking to get ahold of Sen. Lindsey Graham, now might be your chance.

Speaking to a crowd of more than 500 people in Bluffton, South Carolina, on Tuesday, real estate mogul and GOP presidential contender Donald Trump read out his fellow presidential contender’s cellphone number.

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Trump said Graham, who represents South Carolina, gave him his business card several years ago, saying the “total lightweight” had been seeking his help for a deal with Fox News Channel.

Trump told the audience he found the card recently and then proceeded to give out the phone number on it.

Trump encouraged the audience to give the number a call. CBS2 called the number and confirms it was indeed Graham’s number — his voicemail box was full.

A Politico reporter reached Graham at the number. “I wonder what caused that,” the senator said about the influx of calls.

Graham tweeted Tuesday saying he was probably getting a new phone.

Trump also called Graham a “stiff” and an “idiot.”

“Here’s a guy, in the private sector he couldn’t get a job, believe me,” Trump said.

Trump’s latest personal attack came after Graham called him a “jackass.”

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“I don’t care if he drops out. Stay in the race. Just stop being a jackass,” Graham said Tuesday on “CBS This Morning.”

Trump has generated headlines since jumping into the presidential race for saying Mexican immigrants are rapists and drug smugglers and for dismissing Republican Sen. John McCain’s reputation as a war hero. “I like people who weren’t captured,” he said of the 2008 presidential candidate who spent five years as a prisoner of war after his plane was shot down in Vietnam.

Polls, meanwhile, show Trump’s straight talk is making him a strong contender, CBS2’s Jessica Schneider. A Monmouth University poll conducted over the weekend had Trump trailing only Wisconsin Gov. Scott Walker (22 percent to 13 percent) for the GOP nomination.

But does he have staying power?

“It’s the Trump summer,” said political analyst Larry Sabato. “But when people get close to voting, they’ll get serious, because both of our major parties want to win.”

An editorial in the Des Moines (Iowa) Register calls Trump unfit to hold office. The newspaper said: “He has become ‘the distraction with traction’ — a feckless blowhard who can generate headlines, name recognition and polling numbers not by provoking thought, but by provoking outrage.”

As CBS2’s Jessica Schneider reported, even President Obama weighed in on Trump’s trash talk with Jon Stewart on The Daily Show.

“I’m sure the Republicans are enjoying Mr. Trump’s dominance of their primary,” the President said.

Trump says his no-holds-barred rhetoric is exactly what the campaign — and the country — needs.

“(Jeb) Bush said my tone’s not nice,” Trump said. “My tone! I said: ‘Tone? We need tone. We need enthusiasm. We need tone!'”

He also defended his comments about Mexican immigrants Tuesday, saying he employs hundreds of them, but stressed he wants people to enter the country legally. He also slammed McCain again, saying McCain doesn’t have a sound immigration policy.

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