GOP presidential hopeful Lindsey Graham said Thursday that Republican front runner Donald Trump has tapped into America's frustration with Washington, but called his rival's policies "gibberish."
In an interview on CNBC's "Squawk Box, the senator from South Carolina criticized what he sees as Trump's solution to illegal immigration.
"I have no idea how you get 11 million people to walk back where they came from. Then we decide who we let back in. That's not an immigration solution," Graham said.
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Graham said Trump's candidacy will lose steam "when the Republican party thinks about winning in 2016." He said Trump's disparaging remarks that Mexican immigrants are rapists and drug dealers makes the GOP's problem attracting Latinos more difficult.
"Demagoguery is taking hold again on immigration. Everything is amnesty, crazy solutions to real problems," he said. "I hope the desire to win will take over the desire of being angry."
There's certainly some bad blood between Trump and Graham, after the former gave out the senator's private phone number last month. This was in apparent retaliation for Graham calling Trump a "jackass" for saying Sen. John McCain was not a war hero because he was taken prisoner during the Vietnam War.
Graham did not make the cut for last week's prime-time Fox News debate. He was on stage at the earlier event with six other candidates whose polling numbers were not in the top 10 among the crowded GOP field.
US needs to get 'off track from being Greece'
"The sole purpose of my presidency is when it comes to the economy ... to get us off track from being Greece," he said. "Take something like Simpson-Bowles, dust it off, and get a bipartisian [debt reduction] solution."
The often-cited Simpson-Bowles plan to reducing the nation's debt—which fell short of approval from the bipartisan panel back in 2010—was created by Republican Alan Simpson and Democrat Erskine Bowles, co-chairs of President Barack Obama's debt commission.
"The economy is going to crash in about 20 to 30 years because 80 million baby boomers are going to go into retirement," Graham said, making a case for how Republicans can prevent that.
"Republicans have to do revenue," he said. "We have to flatten out the tax code; take some of the money we generate by eliminating deductions to pay down debt, younger people have got to work longer, means test benefits for people of my income."
Graham also took rival Chris Christie to task—saying that when the New Jersey governor signed the Grover Norquist pledge not to raise taxes he hamstrung Republicans in working with Democrats on reducing the debt.
Still, he said, "I love Chris Christie. He's a good guy."
"Nobody's talking about raising tax rates. But we are talking about eliminating deductions and applying some of that to the debt," said Graham. "I'd be willing to do that if Democrats would age-adjust and means-test."
Graham on Iran deal, Islamic State insurgency
Graham, a member of Senate Armed Services Committee, was highly critical of the Iran nuclear deal crafted by the Obama administration and other world powers. "It's not between this bad deal and war. It's between a bad deal and better deal," he said.
He said the next president could get better concessions from Iran if sanctions remained on the table. "Almost anybody could get a better deal," said Graham.
"The Iranians know they would lose a war with us," he said. "If they try to break out [and develop a nuclear weapon] and we don't go to war, we're idiots."
A vote in Congress on the agreement to curtail Iran's nuclear program in exchange for sanction relief is set for a September. Earlier this month, powerful senate Democrat Chuck Schumer, the most influential Jewish voice in Congress, decided to oppose it.
Graham said he wants the U.S. to take a more aggressive role in squashing the rise the Islamic State terrorist group.
"We need boots on the ground in Iraq and eventually Syria to keep ISIL from attacking our homeland," he said. "I think most Americans are worried about another 9/11, and one is on the way if we don't up our game and go on the offense over there."