Donald Trump and Ted Cruz have spent most of the presidential race avoiding direct confrontations with each other. But the men are in first and second place in the polls, so that's been straining the love.

This week, as NPR Politics put it, Trump went "birther" on his rival, questioning whether Cruz is even eligible for the White House because he was born in Canada. (Many legal scholars say he is.)

But as the two candidates continue to lead GOP polls, some observers on the Republican side have expressed fear that either man — and Trump, in particular — will win the nomination. And that concern has not been limited to those in the party's establishment.

Cue Matt Kibbe, former head of the tea party group FreedomWorks. Kibbe — who left FreedomWorks to lead Concerned American Voters, a superPAC supporting Sen. Rand Paul — says that while Trump taps into some of the same anxiety shared by tea partiers over political dysfunction, the businessman's rise also signifies something much more dire.

"I think if Donald Trump becomes the nominee, you're almost guaranteed a third-party challenge, perhaps from the Republican side and the Democratic side," Kibbe tells NPR's Scott Simon. "And it might also lead to the death of the Republican party."


Interview Highlights

On the future of the candidate he supports, Rand Paul

I think we would all be mistaken if we made any bold predictions about what's going to happen in Iowa and New Hampshire. It's a particularly tumultuous primary season, and if you go back and look at 2012, which was also pretty unpredictable, the people that were winning at this point ultimately did not win in Iowa. I think the ground game matters more than polling, and we'll have to see what happens.

On what's behind Donald Trump's rise

There's two things going on. One is a clear sense of economic anxiety and the feeling amongst a lot of voters that the country's headed in the wrong direction — combined with the sense that Washington doesn't really give a damn.

The other thing that's going on, which I think is more fundamental, and I think both Republicans and Democrats are struggling to understand this, is a transformational moment in politics. It's more disintermediated; the party bosses no longer get to decide who the choice is. And both the RNC [Republican National Committee] and the DNC [Democratic National Committee], I think, are struggling with this new reality.

With social media, with the ability to raise money online, with the ability to drive your own message and organize your own get-out-the-vote machine without the party's blessing, all sorts of candidates have become competitive. Donald Trump is definitely part of that, although he's sort of the odd man out because he's more of a cult of personality.

On whether Trump is tapping into tea party sentiment

He's definitely tapping into the anxiety that Washington is broken and that the economy is headed in the wrong direction. But the fundamental difference between the way I think about the tea party — and I'm a card-carrying member of the tea party — is that we talked about the rule of law and we worried that President Obama was very much overstepping the powers of the presidency.

We wanted to see the power back in the hands of the people. And Donald Trump clearly doesn't care about that stuff. He on a regular basis makes it very clear that as president he would do what's necessary to get the job done.

On what Trump's rise says about the two major political parties

I think they're sort of walking on eggshells right now, and it goes back to this question about disintermediation. The two-party system has very much been dependent on the ability of party bosses to control the message, to control the money, to control who the candidates are from the top down. And the party that best understands that that world is no longer there is best going to flourish in this new environment.

I think in some ways Donald Trump is a creation of the Republican establishment's unwillingness to accept this new world.

On whether Trump has been a beneficiary of the tea party's rise

I've looked at the data of this, and it depends on how you define the tea party. I talk to tea partiers every day, and he definitely has support from some of them and ... some of his strongest opposition comes from the tea party.

I think it gets to this question of executive power. But I also think that he's drawing from a lot of Democrats, a lot of independents, a lot of people that have not been participating in the political process before.

To me, that's part of the interesting part of this new world. You know, can we actually enfranchise more voters, can we engage more people in this process?

And I should say, we should mention that the same dynamic is happening on the Democratic side. Bernie Sanders is in large part tapping into some of those same anxieties. He has, oddly enough, some of the same positions as Donald Trump on key issues ... on foreign policy, on immigration. Bernie Sanders has a history of being opposed to new immigration. It's sort of that closed-system view that our best days are behind us.

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