Welcome to the NewsHour. President Trump proved his political power in Texas last night as his endorsed candidate in the state's U.S. primary runoff won in a landslide.

Attorney General Ken Paxton secured the Republican nomination in Texas, beating incumbent Senator John Cornyn by nearly 30 points.

President Trump is the leader of our party and his endorsement in this most power,

is the most powerful force in politics.

And I'm honored to have his support, and I look forward to working with him in the Senate

to deliver for Texas.

Cornyn, who has represented Texas in the Senate for more than 20 years, said he would support Paxton in the general election.

There's a simple rule in elections. You've heard me say it before, and that is the candidate who gets the most votes wins.

The party and the majority gets to govern, and my hope is to keep my party in power for generations.

Paxton will face Democratic nominee James Tolariko in the fall in what's set to be one of the nation's marquee midterm races.

For analysis of last night's results in Texas, we're joined now by Brandon

Roddinghouse. He's a professor of political science at the University of Houston and co-host of

Houston Public Media's Party Politics. It's great to have you here. Thanks for being with us.

And my pleasure. You have described John Cornyn's loss as the end of the Bush-era Republican model in Texas.

Is this primarily about Donald Trump, or is this a deeper ideological realignment within the GOP?

It's a good question. I think it's a little bit of both. Obviously, John Cornyn symbolized the traditional Texas GOP that came to power in the 1990s, they were able to convince voters

that small government with low taxation was the way to go. That changed Texas and frankly

changed the country. The emergence of Donald Trump definitely exacerbated some of what was

already happening in Texas, which was that it was a very conservative place. And the model in Texas is adapt or die.

And essentially, Republicans are following that mantra,

attempting to find the more conservative wing of the party, embrace them, and ride that to victory.

Ken Paxton, as you will know, he has survived impeachment, indictment, FBI scrutiny, repeated ethical

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