As he prepares to take the stage Wednesday for the second televised Republican presidential debate, Kentucky Sen. Rand Paul is making it clear he wants to use the airtime to go after Donald Trump again.

“I think he deserves both barrels,” Paul said in a Tuesday afternoon interview with The Daily Caller. “I want to make sure everyone in the whole country knows he’s a fake conservative.”

Paul went on offense against Trump harder than any other Republican in last month’s Fox News debate. But despite the attacks, Trump’s numbers have only gotten stronger while Paul’s have faded.

Previewing his argument against the New York businessman at Wednesday’s Reagan Library debate in California, Paul said voters just need more time to learn about Trump’s past positions: “I think ultimately when voters fully grasp who he is and what he supports, I think they’ll run away with their hair on fire.”

“The message hasn’t penetrated yet that Donald Trump isn’t one of us,” Paul argued. “He’s barely a Republican. He’s been a Democrat. He’s been a huge supporter of Harry Reid, Charlie Rangel.”

Paul has been criticizing Trump for acknowledging that he gives money to politicians because he wants to call in favors down the road.

“He’s the consummate insider,” Paul said, “buying and selling politicians.”

Even though he has seen his numbers go down, the senator says he is “comfortable with where we are” because “we have our own niche that’s carved out quite well.”

“I’m the only one on the stage who has actually put forward a budget that balances,” Paul said. “I’m the only one really on the stage who stood up in defense of privacy, through the Fourth Amendment right to be left alone. I’m the only one on the stage who says, ‘you know what, I’m not for sending our sons and daughters back to war in Iraq.'”

Asked about Ben Carson and Carly Fiorina — two other Republicans who, like Trump, have never served in office and have seen their poll numbers rise recently — Paul declined to criticize his rivals.

“I don’t know enough about either one of them to know what their positions are on policies,” he said. “But I think they do represent a significant frustration of everybody with Washington. And I’m part of that. I ran for office because I was unhappy with what’s going on in Washington and continue to be.”

Part of Paul’s challenge now is to convince voters that he’s a true outsider. His campaign slogan is “defeat the Washington machine.”

“I continue to be one of the leading proponents for term limits,” he said. “Because I think the only way to get our government back is actually to have more changeover in office.”

The campaign, he said, is also actively working to remind people he’s been an eye surgeon for 20 years and has spent most of his life outside politics.

“It takes a while,” he said. “Probably 1 in 100 voters knows I’m a physician so we do want my entire biography to be out there.”

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