When Everybody Was Distracted, Marco Rubio May Have Just Blown Up the Republican Party

Fox News moderators ended the network's Thursday-night Republican debate by asking frontrunner Donald Trump's three rivals whether they would support Trump if he became the party's nominee.

"I would vote for Marco Rubio in Florida, for John Kasich in OH, and for Ted Cruz or whichever one of the other two contenders has the best chance of beating Mr. Trump in a given state", he said.

"I'll support Donald if he's the Republican nominee", Rubio said.

Republican leaders and mainstream voters were watching Friday for signs that Thursday's attacks on front-running presidential candidate Donald Trump, one of the most extraordinary days in party history, had blunted his campaign for the party's nomination.

While Cruz and Rubio relied on directly challenging Trump, Kasich continued to play a role he says people have complimented him for: being the adult in the room.

"When they're done with the yoga, can I answer a question?"

Marco Rubio: Rubio's new tact - sort of Trump light - isn't coming across well.

Rubio, 44, and Cruz, 45, questioned Trump's immigration policy and his use of foreign workers at his exclusive Mar-a-Lago resort in Palm Beach, Florida.

Ahead of the speech, much of which had been previewed in excerpts, Trump dismissed Romney in television interviews and posts on Twitter, calling him "a failed candidate" who had "begged" him for an endorsement in 2012.

In one moment of levity, Texas Sen.

Trump disparaged Romney in a series of tweets, including "I am not a Mitt Romney, who doesn't know how to win".

Holding up both hands to the audience, the Republican said: "He (Rubio) referred to my hands, "if they're small, something else must be small".

Cruz, as he has done for weeks, also attacked Trump for having supported and donated money to Democrats in the past. We need highly skilled people in this country.

Attacking Trump's pledge to "make America great again", Clinton said "America never stopped being great!". Romney says he'd rather see someone other than Trump be the nominee outright on the first ballot but if that doesn't happen he'd like to see an open convention.

"Mr. Trump is directing our anger for less-than-noble purposes". They are the last two anti-Trump candidates standing in what has been a bruising nomination battle. With Carson's exit from the race this week, the field of Republican candidates has now been narrowed to four, including Ohio Gov. John Kasich.

Trump came into the debate off a strong showing in nearly every Super Tuesday state and with a healthy lead in delegates. According to Romney, if the Republicans end up choosing Trump as their nominee, "the prospects for a safe and prosperous future are greatly diminished".