Newsletter: Essential Politics: Cruz in good spot heading toward Christmas

As the presidential campaign moves toward a brief holiday respite, the latest Republican debate clearly illustrated where the fault lines lie within the GOP.

The Democratic candidates headed for one more hidden-on-Saturday-night faceoff as Hillary Clinton strengthened her front-runner status. And Sen. Bernie Sanders' campaign got tagged with the season's first campaign dirty trick.

Good afternoon, I'm David Lauter, Washington Bureau chief. Welcome to the Friday edition of our Essential Politics newsletter, where we review the past week of the presidential campaign and highlight stories that provided particular insight.

The Republican divide

The GOP debate on Tuesday night drew another large audience -- 18 million viewers. As Cathy Decker noted in her analysis, the face off likely did not change many voters' minds. But it did clarify which candidates see each other as immediate threats.

The two freshman senators in the race, Ted Cruz of Texas and Marco Rubio of Florida, repeatedly clashed. Noah Bierman took a close look this week at the divergent paths taken by the two men, whose biographies have remarkable similarities but whose political personas are very different.

Chris Christie, the New Jersey governor whose campaign has appeared to come back to life in New Hampshire lately, sought to position himself as tough, like Donald Trump, but with more experience and steadiness.

Jeb Bush, the one-time front-runner who has sunk into the second tier, tangled with Trump.

"You can't insult your way to the presidency," Bush memorably said.

Whether that's true remains to be seen. Nothing that Trump has done or said in the past couple of months has shaken his hold on the 30% or so of Republican voters who consistently back him. On the other hand, his unfavorable image with the wider electorate has also remained solid. He's a candidate whose support has a high floor and perhaps also a low ceiling.

Among Trump's rivals, Cruz enters the holiday season in an enviable position. He leads the polls in Iowa, benefits from the divide among more moderate candidates competing in New Hampshire and is well positioned in the Southern states that come up quickly thereafter. And while his Senate colleagues deeply dislike him, many establishment GOP figures may decide he poses less of a problem than Trump.

Rubio has pursued a very different strategy than Cruz. He has invested less in on-the-ground organization in Iowa and has tried to appeal to a broader range of voters than Cruz, who emphasizes his hard-line conservatism. That approach has yielded some benefits -- a wide range of voters list Rubio as their second choice -- but has yet to put him in the lead in any of the early states.

Dirty tricks?

Over on the Democratic side, Clinton has widened her lead in Iowa, according to recent polls, and has erased Sanders' one-time lead in New Hampshire.

And on Friday, her campaign received a pre-Christmas gift as the Sanders campaign was caught up in a mini-scandal over campaign data. As Evan Halper wrote, one of Sanders' campaign aides was caught breaking into voter files from the Clinton campaign. The Sanders aides gained access to the data because of an apparent software bug in the system used by the Democratic National Committee's data contractor.

The DNC has suspended Sanders' access to the voter data, which is a big problem for any campaign. Moreover, the problem could scuff up Sanders' image, which has been built, in part, around his declaration that he doesn't engage in negative campaigning.

Halper also took a look this week at the declining fortunes of corn-based ethanol. For years, Iowa's early position on the primary calendar has served to protect the subsidies that the government provides to ethanol made from corn. But Iowa's Republican voters don't care as much, and the special deal for ethanol may be on the way out.

Christi Parsons and Michael A. Memoli took a close look at President Obama's renewed focus this fall on guns. The key moment occurred after a mass shooting in Oregon in October. As Obama looked over his prepared remarks, he warned aides he planned to go off script, they report.

"I’m just going to riff off it," he said. "I'm pissed."

We’ll be covering the Democratic debate Saturday night. Keep an eye on our politics page for detailed analysis over the weekend and follow us on Twitter at @latimespolitics.

What we're reading

Did Rubio violate Senate ethics rules by using campaign funds to pay the ghostwriter for his book? S.V. Date lays out the evidence in National Journal. His story quickly prompted an ethics complaint about Rubio from a Washington, D.C.-based liberal watchdog group.

And in the category of trends that have more effect on the election than most news stories, Gallup reports that the percentage of Americans saying that it's now a good time to find a quality job has hit the highest level since 2007, before the Great Recession.

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.

Send your comments, suggestions and news tips to politics@latimes.com.