Donald Trump.

And Jordan Klepper, he went to find out why.

You've heard the news-- Donald Trump is on fire.

Donald Trump, fresh off a landslide victory

in New Hampshire...

His success has baffled the mainstream media,

but it turns out the secret to Trump

has been right under their noses the whole time.

This is a circus unlike anything that we have seen

in modern American politics.

This is the greatest show on Earth.

He's the greatest show on Earth.

Now, if you want to understand

the circus that is Donald Trump,

don't ask these idiots.

Ask the guy with a sword down his throat,

circus performer Adam Realman.

People like the danger element of a circus and a sideshow.

You know? When the lion tamer

sticks his head in the lion's mouth...

tell me, you want to see the lion just chomp his head off.

-Yeah. -The audience, I think,

always wants to know that this stuff is real, and it is real.

We're watching a loaded gun on stage,

and it could go off at any moment

and say, "Mexicans are rapists."

Boom. It could say anything.

-So there's a dangerous... -Mexicans are rapists?

Okay, so maybe he hasn't been to many Trump events.

But Realman taught me that the greatest show

must have a ringleader who can work a crowd.

-You got to give 'em the pitch. -You have to impress them.

You got to impress your crowd. Exactly.

-Your poll number, super hot. -Correct.

I'm leading every poll nationwide...

-You're the best. -That's it...

-Best businessman you've ever seen. -Yes.

I make great deals.

Look at this show-- this is the greatest show on Earth.

Ladies and gentlemen, we are going to...

Hey, let's bring out the snake charmer.

And we bring out the snake charmer...

-You bring Palin out. -Okay.

You betcha!

Has to be something that an audience will want to see.

Everybody had a good old time, you bought a hat--

-hell, I want to see this freak again. -Exactly.

This guy got it-- Trump really is

the greatest show on Earth. Right, Adam?

Well, you know, by calling him the greatest show on Earth,

you're kind of insulting a lot of the circus world.

Okay.

Regardless, I had to see Trump up close.

So I headed to one of his rallies

and got to hear from some die-hard Trump-eters.

I think he is the only candidate on the Republican side

who's actually gonna build a wall.

And who's he gonna make pay for it?

He's gonna make China-- you know, people say,

oh, you can't make China pay for it.

You know what? That's a bunch of horse crap.

It's pretty easy to make China pay for it.

China will be paying for the wall.

Shouldn't Mexico pay for the wall?

-Oh, my... Mexico. Sorry. -Either way.

One of those (bleep) countries is paying for that wall.

One of those countries is paying for that wall.

Donald Trump is inaugurated,

he becomes president of the United States--

what's behind that curtain?

-Defea-tion of ISIS? -Yes.

-What should we do to ISIS? -Bomb the (bleep) out of them.

Where, officially, should we bomb ISIS?

Probably, like, Israel area, but not, like...

not necessarily there, but around the area.

I think he's gonna help with the ISIS.

What's he gonna do with the ISIS?

-He can't tell us right now. -If he tells everybody,

then the next thing you know, somebody else is gonna copy

what he says.

They knew their Trump.

Once I was under the big top, we were all groovin'

to Trump's power playlist,

which included "Tiny Dancer," like, eight (bleep) times.

Finally, there he was, and he wasted no time

shining the spotlight on the main event: himself.

It takes guts to run for president, believe me.

We've hit number one in the polls every single week.

I've been on the cover of Time magazine so much lately.

When I was on last week, I didn't even know

they were putting me on the cover-- can you imagine?

That's when you're really hitting it big.

He made the audience recoil at the freak show.

And look at back there, look at the press.

Turn around and look at these people.

-(crowd jeering) -Look at them.

(chuckles) They start booing.

He whipped the crowd into a frenzy

with a high-wire act of political incorrectness.

She said he's a pussy. That's not...

(whooping)

(cheering)

Pussy! Yeah!

And then something strange happened.

We're gonna do something that's going to be,

whether you like Dwight Eisenhower,

no matter what you do, Dwight Eisenhower-- I like Ike.

-Everybody says... -He started to meander.

I just asked for tickets. I wanted tickets for the debate.

...no post office in Washington, DC, right?

-People got bored. -(Trump speaks indistinctly)

But... then, like any great showman,

he pulled them back in with his greatest routine--

a feat of xenophobic strength.

Who the hell is gonna pay for the wall?

What?

Mexico!

Ha-ha! Classic bit.

Trump had delivered.

I laughed, I cried,

I reinvigorated my irrational fear of foreigners.

(distorted): Mexico!

I even jockeyed for selfies

with a couple of reality TV stars.

Donald, great joke!

Great joke!

Ivanka! Smile! Smile!

Smile!

Hey...!

-(shutter clicks) -Got it.

A memory that will last for...

possibly four years.