Good morning, NBC News readers.

The Trump administration signals a sharp shift in immigration policy, another Democrat enters the 2020 race with a phone call to his mom, and Virginia wins it all.

Here's what we're watching today.

Stephen Miller is lone survivor at center of White House Homeland Security chaos

And then there was one.

Amid the chaotic power struggle that led to Kirstjen Nielsen's ouster as Homeland Security secretary, one White House adviser is the obvious winner: Stephen Miller.

The iconoclastic hard-line young policy aide to President Donald Trump, hated by the left and celebrated by the extreme right, has survived all his rivals.

Now Trump's immigration policy, which will be the president's central 2020 campaign issue, belongs to him, NBC News' Jonathan Allen writes.

The director of the U.S. Secret Service, Randolph Alles, also announced he is leaving his position, in a further sign of the Department of Homeland Security shakeup.

But as the Trump administration hardens its stance on immigration, it will still have to contend with challenges from other parts of the government.

A federal judge in California issued an order Monday blocking the Trump administration's policy of returning some asylum-seekers to Mexico while they wait for a court appearance.

Any appeal of the decision would be heard by the Ninth Circuit Court of Appeals, which Trump has repeatedly blasted as a "disgrace" for ruling against his policies.

Woman arrested at Mar-a-Lago had device to detect cameras

A Chinese woman recently arrested at President Donald Trump's Mar-a-Lago club lied repeatedly to Secret Service agents while carrying computer malware unlike anything a government analyst had ever seen and had more than $8,000 in cash in her hotel room, federal authorities told a judge Monday.

Yujing Zhang, 32, was found to be carrying two Chinese passports, four cellphones, a laptop computer, an external hard drive and a thumb drive containing the malware when she was arrested at the president's Palm Beach resort.

Virginia wins NCAA title in OT thriller

The Cavaliers, a year removed from suffering the worst loss in NCAA tournament history, are national champs after defeating Texas Tech, 85-77 in overtime.

Virginia's Kyle Guy celebrates after the Cavalier's NCAA win. Streeter Lecka / Getty Images

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Plus

Sci-fi no more: Artificial blood vessels that come to life could improve medical care.

Artificial blood vessels that come to life could improve medical care. Israeli voters head to polls to choose between "King Bibi" Netanyahu and a "new path."

$4 gas? That's right. Much of the country is headed that way. Here's why.

The Trump administration scuttled a landmark deal enabling Cuban baseball players to play on Major League Baseball teams and declared it illegal.

California Rep. Eric Swalwell announced he is running for president during an appearance on "The Late Show with Stephen Colbert." His mom said he has her vote "as long as none of his other brothers are running against him."

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THINK about it

Stephen Miller consolidating power will make things much worse for migrants, Julio Ricardo Varela writes in an opinion piece.

Science + Tech = MACH

The first all-female spacewalk was supposed to be a giant leap for women. But the recent cancellation of the scheduled walk is another entry on the timeline of challenges women of NASA have had to overcome.

Live BETTER

What's in the meatless "Impossible Whopper"? Is it any healthier than the original? A registered dietitian weighs in.

Quote of the day

"Stephen Miller's fingerprints are all over Secretary Nielsen's resignation letter."

— Dan Eberhart, a major Republican donor who is in touch with administration officials.

One nice thing

In honor of Autism Awareness month, Sesame Street introduced the family of Julia, a character with autism, hoping to tackle the sense of isolation some families may feel.

Thanks for reading the Morning Rundown.

I'd hope my mom would give me a more ringing endorsement if I called saying I was running for president. But who knows — no favorites!

If you have any comments — likes and dislikes — drop me an email at: petra@nbcuni.com

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Thanks, Petra