Newsletter: Essential Politics: The week the dam broke

For months, the elected officials, consultants and big-money donors who make up the Republican establishment had kept their concerns about Donald Trump pent up behind a mental dam: Sooner or later, they kept telling themselves, the billionaire provacateur would fade away.

This was the week the dam broke.

Good afternoon, I'm David Lauter, Washington Bureau Chief. Welcome to the Friday edition of our Essential Politics newsletter, where we review the major developments of the past week and highlight some stories that go beyond the daily headlines.

Trump's announcement that as president he would ban most Muslims from entering the U.S. jolted the presidential campaign. Not only did Democrats denounce the idea, but a series of high-level Republicans, including House Speaker Paul D. Ryan of Wisconsin and Senate Majority Leader Mitch McConnell of Kentucky did, as well.

At least some Republican operatives told themselves that this time, finally, Trump's words would sink him.

Within days, however, polls made clear how wrong that assumption was. Trump has held on to his lead among Republican voters both nationally and in early-voting states, such as New Hampshire.

As the threat of terrorism has pushed aside the economy as the top concern, at least among Republicans, Trump's image as a strong leader has outweighted voter concerns about his temperament. And the anger that many Republican voters feel toward their party's establishment has made Trump all but impervious to attacks by elected officials. If anything, their jibes may strengthen him.

As they have shed their comforting denial about Trump's staying power, Republican leaders, Mark Z. Barabak wrote, have recognized that they face an agonizing problem. Trump remains deeply unpopular in the broader electorate. But if he has a low ceiling on his support, he also has a high floor: Many of his supporters are ardent.

If Republicans alienate Trump's backers, he could make good on his repeated threats to run as a third-party candidate. Current polls indicate that he might get around 18% of the vote -- coincidentally the same level Ross Perot received in his effort in 1992.

Perhaps Trump would fade over time as third-party candidates often do. Maybe he would decide he didn't really want to spend the huge amount of money such a race would cost. But any serious independent run by Trump would almost surely sink the GOP nominee.

And if Trump were to win the GOP nomination, party strategists fear he would drag down the entire Republican ticket, leading to loss of the party's Senate majority at the least.

As Cathy Decker wrote, ignoring Trump didn't work, so now what?

Who are Trump's supporters? Polls tell us that they are predominately male, blue-collar, not deeply religious -- people like 56-year-old Bruce Goacher.nbsp Michael Finnegan spent the day with Goacher in Davenport, Iowa, talking extensively about why he supports Trump. It's a terrific look at the attraction the Republican front-runner holds for his backers.

“He didn't have to work as hard as I did with my callused hands,” Goacher said. “If a man can become a billionaire without having to work that hard for it, he's evidently a pretty smart man, money-wise, and the United States has to be run as a business.”

If Trump does fade, many of his opponents in the GOP are pinning their hopes on Sen. Marco Rubio of Florida. As a first-term senator, Rubio has a limited record. His biggest effort, by far, was the deal that, for a little while, seemed like it could break the stalemate over immigration reform. Lisa Mascaro took a careful look at what the immigration saga can tell us about Rubio's skills.

On the Democratic side, Hillary Clinton and her rivals have all gone all-in on gun control. That's a break from years of belief that the issue was political poison. On the face of it, the trend is somewhat surprising, since polls do not show gun control gaining support in the electorate. If anything, the reverse is true. Evan Halper and Barabak explain the Democratic strategy and why the party thinks it's a good bet.

Finally, while the week was a momentous one on the presidential campaign, an even bigger development may be coming from the Supreme Court. As David Savage explains, a majority of the justices seem ready to at least start down the road toward a huge shift in political power in the U.S., one that would potentially bolster the GOP.

What we're reading

Molly Ball in the Atlantic took an excellent look at how Trump’s anti-Muslim appeal and the reaction to it reflects the split within the Republican party.

And the Washington Post's Robert Costa and Steven Ginsberg had breakfast with Trump at a country club he owns near Washington, D.C. The interview makes for fascinating reading.

That wraps up this week. On Monday, my colleague Christina Bellantoni will be back with the daily newsletter. Until then, keep track of all the developments in the 2016 campaign with our Trail Guide, at our politics page and on Twitter at @latimespolitics.

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