Arnie Seipel

Updated at 11:17 p.m. ET

Secretary of Homeland Security Kirstjen Nielsen is leaving her post, President Trump announced Sunday as he continues to focus on restricting border crossings amid a recent surge. Nielsen had recently warned a congressional panel of a "catastrophe" on the southern border after the number of crossings hit a 10-year high.

The partial government shutdown is now the longest in history, as Saturday marks Day 22. The previous record was 21 days, set in the winter of 1995-96 when President Bill Clinton and House Speaker Newt Gingrich were at odds over budget cuts.

Updated at 10:12 p.m. ET

Judge Brett Kavanaugh issued a mea culpa of sorts on the eve of a key Senate vote that could determine whether or not he reaches the Supreme Court, admitting in an op-ed that his testimony last week forcefully defending himself from sexual assault allegations "might have been too emotional at times."

Updated at 9:30 a.m. ET

President Trump is facing calls to act in the wake of the latest mass shooting, which killed 17 people Wednesday at a high school in Florida, and the White House is not ignoring them. The president will participate in a pair of listening sessions on school safety this week, and on Monday morning the White House said he supports efforts to improve the federal background check system, something Congress has expressed broad support for without acting on after past shootings.

Updated on Dec. 22 on 12:02 p.m. ET

Congressional Republicans delivered on their first major legislative accomplishment of the Trump era on Wednesday, when the House voted 224-201 to pass a $1.5 trillion tax package. The bill cuts individual rates for eight years and slashes the top corporate tax rate to 21 percent permanently.

Updated at 6:17 p.m. ET

Congress has voted to avert a partial government shutdown that could have come Friday night.

Updated Dec. 2 at 11:57 a.m. ET

The Senate narrowly approved a $1.4 trillion tax overhaul early Saturday morning following a day of procedural delays and frustration.

The legislation, which would cut the top corporate tax rate to 20 percent and lower taxes for most individuals, narrowly passed in a vote of 51-49. Tennessee Republican Bob Corker was the only Republican to vote against the legislation, joining every Democrat and both independents in opposing the sweeping overhaul of the nation's tax laws.

Updated at 11:20 a.m. ET

Senate Republicans continued maneuvering to pass their overhaul of the nation's tax code on Friday, possibly working around concerns by stern deficit hawks after an official estimate on Thursday said that the economic growth spurred by the plan would still leave a $1 trillion hole in the deficit.

Updated at 4:12 p.m. ET

The Trump administration is putting North Korea back on the State Department's list of state sponsors of terrorism. President Trump says the move "supports our maximum pressure campaign to isolate this murderous regime."

President Trump told reporters on Monday that the Treasury Department will officially announce additional sanctions and penalties on the North Korean regime on Tuesday.

The Trump administration is updating its travel ban, just hours before it was set to expire. In a proclamation signed by President Trump on Sunday, the travel restrictions now include eight countries, a couple of which are not majority-Muslim, as had been the case with all the nations in the original ban.

Updated at 4:30 p.m. ET

Republicans are facing even more uncertainty when it comes to finding the votes to pass a bill to repeal major parts of the Affordable Care Act, as familiar voices in divergent wings of the party show just how difficult it is for the GOP to unite on the issue of health care.

Updated 3:30 p.m. ET

With their health care bill facing a perilous path, Senate Republican leaders have decided to push off a vote until after Congress returns from next week's July Fourth recess, GOP aides confirm to NPR's Susan Davis.

With little power left in Washington, Democrats set out on Sunday to make a big statement against GOP efforts to repeal the Affordable Care Act with rallies in dozens of cities.

It's also a step for the party toward regaining its footing after grassroots efforts in 2016 failed to keep the White House in Democrats' hands.

President-elect Donald Trump won a convincing electoral vote victory on Nov. 8, but he is claiming falsely that widespread voter fraud cost him the popular vote.

The latest totals show Hillary Clinton leading Trump in the popular vote by more than 2 million. Trump tweeted on Sunday afternoon, "I won the popular vote if you deduct the millions of people who voted illegally." He did not provide evidence to back up that claim, and Trump's representatives did not immediately respond to a request for more information.

Updated at 7:30 p.m. ET

Federal agents now have a search warrant they need to examine the thousands of emails found on a computer belonging to former U.S. Rep. Anthony Weiner that could be pertinent to the investigation of Hillary Clinton's personal email server, sources familiar with the matter tell NPR's Carrie Johnson.

Weiner is the estranged husband of Clinton aide Huma Abedin.

Perhaps the clearest sign that Ted Cruz is seriously challenging Donald Trump's dominance in the Republican primary race is that Trump has started attacking him.

It started Friday morning. Just about an hour before Ted Cruz addressed religious conservatives gathered for the annual Values Voter Summit in Washington, House Speaker John Boehner — one of the renegade Texas senator's nemeses in the Washington establishment — called it quits.

And Cruz was nimble, adjusting his speech to give the activists he was speaking to credit:

Ted Cruz knows how to work this room. His supporters were out in force with T-shirts and buttons, building on the great reception of his speech.

This story is part of the New Boom series on millennials in America.