Updated

Yesterday was a remarkable day in the world of politics. The front-runner Donald Trump was attacked by the past two Republican presidential candidates. Mitt Romney launched a blistering attack on Mister Trump in a live speech. That was followed by John McCain echoing Romney in a tweet. Then there was last night’s debate.

And what a debate!

The Fox debate in Detroit provided fireworks and fury. It was the first time Trump had interacted with Megyn Kelly since their now infamous exchanges last August.

Philip Rucker, Ed O'Keefe and John Wagner write in today’s Washington Post in a story headlined “Rivals pile on Trump in Republican debate:

The calamity brought upon the Republican Party by Donald Trump was laid bare Thursday by its two most recent presidential nominees, who delivered unprecedented denunciations of the candidate that set the stage for a raucous evening debate.

Mitt Romney awoke from his political hibernation to deliver a sweeping, point-by-point indictment of Trump - of his policy proposals, his business dealings, his erratic judgments, his moral character, and his insults to women, Latinos and the disabled. The former GOP nominee, who sought and accepted Trump's endorsement in 2012, implored Republicans to reject the billionaire he labeled "a phony" and "a fraud."

Trump's three rivals took up similar attacks later Thursday night at a Fox News Channel debate in Detroit in which the ferocious sparring and name-calling revolved almost entirely around the front-runner.

What started with Trump asserting that he was well endowed in a rejoinder to Rubio's campaign-trail joke about his manhood devolved into an ugly affair, with the candidates yelling over one another, at times unintelligibly.

Taken as a whole, the day only served to harden the divisions tearing the GOP apart and raise dire doubts about whether its factions could unite in the general election.

Jenna Johnson writes in the Washington Post in an article called “Blistering attacks upend Trump’s pivot to statesman mode:

First, Donald Trump attacked former Republican presidential nominee Mitt Romney for being a “failed candidate.” Then he turned to “little” Marco Rubio. He angrily listed his recent wins and poll standings. Somewhere in there, he tossed in a “lyin’ ” Ted Cruz.

One of the few people he didn’t attack was Fox News’s Megyn Kelly — whom he famously lit into at a debate in August and with whom he had sparred for months.

Following his big wins Tuesday night, which put him in a commanding position for the Republican nomination, this might have been the night when Trump could safely shift into statesman mode, acting like a presumed nominee instead of a candidate.

Instead, Trump was under sustained grilling — from Rubio, Cruz and the Fox moderators — like never before, as the debate audience cheered on the attacks.

The night started with a joke about the size of Trump’s genitalia — and went downhill from there, often devolving into hard-to-comprehend shouting matches, with Trump repeatedly interrupting his rivals and firing off endless attacks of his own.

At one point, Cruz coached Trump to “breathe, breathe, breathe.” That prompted Rubio to make a joke about yoga and call Trump “very flexible,” a nod to the front-runner acknowledging that he has changed his position on assault rifle bans and visas for foreign workers.

This is what the Republican race and, especially, the debates have become — and there’s no sign that the slugfest will end, even as Trump wins more and more primaries.

Beth Reinhard, Janet Hook and Rebecca Ballhaus write in the Wall Street Journal today that Trump was attacked from all sides last night, “Confronting a furious onslaught by his Republican rivals and the party establishment, front-runner Donald Trump struck back with a barrage of counterattacks at Thursday's debate, demonstrating the same bravado he showed before he had won a single vote.

Although Mr. Trump is drawing closer to the nomination after victories in 10 states, and has said he would strike a more presidential pose, the New York businessman didn't ease up on his penchant for belittling his rivals, interrupting them and dismissing their criticisms.”

Mitt Romney has an interview this morning with our own Neil Cavuto. Neil will discuss the fight with Trump on our show and play a piece of that interview. Romney is also on the Today show.

Lots of live events to cover, though nothing like yesterday’s insanity.

0900EST -- Donald Trump holds a rally. Macomb Community College Expo Center, Warren, MI. LIVE

1030EST -- Sen Cruz holds a rally. Univ of Maine, Orono, ME. LIVE via LiveU

1115EST -- Sen Rubio holds a rally. Topeka, KS. LIVE via LiveU

1300EST -- Donald Trump holds a rally. The Wexford Civic Center, Cadillac, MI. LIVE

1315EST -- OH Gov Kasich speaks. LIVE

1100EST -- Sen Sanders holds a rally. Southern Illinois Univ - Edwardsville, Edwardsville, IL. LIVE via LiveU

1430EST -- Hillary Clinton delivers a policy speech on jobs. Detroit Manufacturing Systems, Detroit, MI. LIVE

This weekend there are more important primaries and caucuses. Both Republicans and Democrats hold elections in Kansas and Maine and Louisiana. There is a Republican caucus in Kentucky and a primary in Puerto Rico. Democrats caucus in Nebraska.

A congressional delegation including Nancy Pelosi are heading to Flint today to hear from families caught up in the lead pipe crisis. It was briefly an issue in last night’s debate.

We get jobs numbers today for February. Analysts are expecting 190,000 jobs were created with the unemployment rate unchanged at 4.9%.

North Korean dictator Kim Jong Un ratcheting up tensions again threatening that he’s ordered his nuclear weapons to be readied for use.

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