The four Republicans face off for a debate in Miami ahead of next week's Floriday primary.
It's never quite that easy.
Donald Trump closed the debate by promising the GOP would easily win the White House in November if the party united around his candidacy.
"The Republican Party has a great chance," Trump said, pointing to the "millions" of people he is drawing to the GOP. "These are people that will win us the election, and win it easily."
The problem is, Trump is actually losing to Democratic front-runner Hillary Clinton in the latest matchup polls.
Clinton beats him, 51% to 38%, in an NBC News Poll/Wall Street Journal released this week.
And the gap has only widened in recent weeks, according to a compilation of polling at RealClear Politics. Trump was narrowly ahead, 45%-43%, in early February.
Which Republicans are competitive against Clinton?
Ted Cruz and Marco Rubio would be tougher for her to beat, the poll showed.
A Clinton-Cruz matchup, 47%-45%, and Clinton-Rubio, 46%-46%, were both razor thin, within the margin of error.
Be smart and unify.
I cannot wait to stand on that stage with Hillary Clinton.
Sometimes being positive isn't all that interesting.... I will continue to run a positive campaign.
Conventional wisdom holds that Donald Trump's runaway success in the GOP contest is due to his appeal to the electorate's anger. Trump says his supporters are motivated by something else: love.
One day after a Trump supporter was videotaped punching a protester at a North Carolina rally, the real estate developer said he did not believe he was inciting violence with his bombastic rhetoric.
He said his backers "love this country" and are dismayed by bad trade deals.
"I see it," Trump said. "They’re so angry. There’s also great love for the country. It’s a beautiful thing."
He added that some of the protesters at his events are "bad dudes [who] have done bad things" and quickly pivoted to praising police officers who help handle security at his mega-rallies.
Sen. Ted Cruz avoided addressing the violent incidents directly, but swiped at Trump for recently asking those at his rallies to raise their hands and pledge to vote for him.
"I think that's exactly backwards," Cruz said. "This is a job interview. We are here pledging our support to you, not the other way around."
Trump said the pledge was mischaracterized by the press and slammed media outlets who compared the audience's outstretched hands to pictures of rallies in Nazi Germany.
"It was a total disgrace," Trump said.
Florida Sen. Marco Rubio affirmed at the Republican presidential debate Thursday that he would oppose all efforts by the U.S. government to curb global warming.
“As far as a law that we can pass in Washington to change the weather, there’s no such thing,” Rubio said in response to a question about the increasing frequency of Miami street flooding due to rising sea levels.
Rubio pounded President Obama for his efforts against global warming, saying all of the legislation and regulation he has pushed in that area would “devastate our economy.”
“America’s not a planet; it’s a country,” said Rubio, who suggested any limitation on carbon emissions in the U.S. would be offset by pollution in China and India.
Republicans have rarely discussed climate change in their debates. This time, CNN moderator Jake Tapper asked Rubio a question suggested by a Republican supporter of the senator, Miami Mayor Tomás Pedro Regalado.
Will you acknowledge the reality of the scientific consensus on climate change, he wanted to know, and pledge to do something about it?
Rubio, whom Democrats have long mocked for not accepting scientific findings on climate change, sidestepped the question.
“One of the reasons why the climate is changing is because the climate has always been changing,” he said. Whatever the cause, he said, he backs efforts to mitigate the flooding in Miami.
Ohio Gov. John Kasich, the only other candidate asked about global warming, said he believed humans cause climate change. He said there was nothing inconsistent about promoting renewable energy and economic growth at the same time. He called for expanding the use of solar, wind and nuclear power, clean coal and natural gas.
“Renewables matter,” he said.
No trash talk from Marco Rubio, who returned to his more optimistic, serious message at the final GOP debate before Florida voters head to the polls next week.
Rubio must win his home state and needs to reassure the upscale, suburban voters who have propelled his campaign but didn't like his hard-hitting insults against Donald Trump. He said this week he regrets some of the language he used.
Read more of our coverage here.
If crowd reaction is any indication, there may be no bigger issue for this South Florida audience than Cuba.
Marco Rubio drew loud applause and whistles when he criticized President Obama's reopening of diplomatic relations with that island's Communist leaders.
"Things are worse than they were before this opening," Rubio said, hitting Obama for not first demanding democratic changes in Cuba.
Rubio, who pointed out that such changes were required of military rulers in Myanmar before the U.S. eased restrictions there, said he would cut diplomatic relations with Cuba until its leaders commit to better protecting human rights.
"I would love the relationship between Cuba and the United States to change," Rubio said, earning huge applause. "But it will require Cuba to change, at least its government."
Donald Trump, who has said in the past that he supports reengaging the Cubans, was asked again about Cuba, this time before an audience that is watching the issue closely.
"I don’t really agree with President Obama," Trump said. "I think I’m somewhere in the middle."
Trump said he is concerned about possibly getting sued by Cuba for reparations if the U.S. embargo against the country is ended. Rubio scoffed at that notion.
"I don’t know how Cuba’s going to sue us, but if they’re going to sue us in Miami, they’re going to lose," he said, a nod to the city's conservative Cuban population.
Trump said he wants to make a deal with Cuba, but one that will favor the U.S. After several questions from the moderators, he was forced to say whether or not he would support closing the U.S. Embassy in Havana, which recently reopened.
In the end, he went with an answer that appeased the audience.
"I would have the embassy closed," Trump said.
One of the starkest divides between Donald Trump and his Republican rivals deepened over how best to handle Islamic State terrorists.
Trump stood by his comment that "Islam hates us" and said he would work to change federal laws, including those that ban waterboarding and prevent the military from targeting civilian families of terrorists.
"You can be politically correct if you want. I don't want to be so politically correct," Trump said. "We have serious, serious problems of hate, we have tremendous hate."
Sen. Marco Rubio shot back: "I'm not interested in being politically correct. I'm interested in being correct.
"We're going to have to work with other Muslims ... to defeat ISIS," he said, using an acronym for Islamic State.
Trump also stood by earlier comments that the United States should be able target the families of terrorists, which is prohibited under federal and international military law.
"We have to obey the laws, but we have to expand those laws," Trump said.
"We have to be able to fight at least somewhat of an equal footing or we'll be a bunch of suckers and they are laughing at us," he said.
Would the other candidates pursue the families of terrorists?
"No, of course not," Rubio said.
"We've never targeted innocent civilians are we're not going to start now," said Sen. Ted Cruz, who called Trump's language "incendiary."
Donald Trump's position on international trade was assailed by Texas Sen. Ted Cruz during Thursday night's debate, leading to one of the more spirited exchanges early on.
Cruz noted Trump's calls for a 45% tariff on foreign goods from countries such as China.
"He backed away from it, but he may come back with a different number tonight," said Cruz, noting "massive tariffs" would damage the economy.
"A tariff is a tax on you, the American people," Cruz said.
Trump said the 45% tariff would be used as a "threat" against other countries.
"It will be a tax if they don't behave," Trump said of China. "The 45% is a threat that if they don't behave, if they don't follow the rules and regulations ... we will tax you. It doesn't have to be 45, it could be less."
Donald Trump has been known to depart from GOP orthodoxy on a host of issues, but on Thursday he said he did not see himself as fundamentally remaking the Republican Party.
Trump said he believed his views are "very similar" to many in the party, but acknowledged one exception.
"I am different in one primary respect, and that’s trade," Trump said. "I feel that we have had horrible negotiators, horrible trade deals. The jobs in this country are disappearing, and especially the good jobs."
That marks a departure from the free-trade advocacy of many in the Republican Party, particularly business interests.
But Trump has broken with the party on other issues in the past, including defending Planned Parenthood for doing "good things," despite being a frequent target for Republicans for providing abortions.
And Trump broke with standard Republican policy in this very debate, saying he would want to "leave Social Security the way it is."
Many in the GOP have called for changes to the programs for future beneficiaries.
I mean a lot of them.
Ted Cruz tried to paint himself as a maverick during Thursday's debate, but ended up pointing to a time he rode a wave of popular opinion.
When Donald Trump vaguely promised to get the federal budget under control by eliminating "waste, fraud and abuse," Cruz saw an opening. He countered that voters want candidates to name specific cuts and pointed to his own vow ahead of the Iowa caucuses to end federal help for ethanol, the corn-based fuel that has long been the untouched third rail of Iowa politics.
But Cruz's attempt to paint himself as a the candidate willing to buck popular sentiment and make hard decisions falls short of the reality of the moment. As The Times' Evan Halper found, even Iowans have begun to move on from ethanol.
Where are the stinging insults? The low blows? The none-too-subtle slights about the size of a candidate's hands or another, more private part of a man's anatomy?
The raucous infighting that has characterized many recent GOP debates is missing tonight. In its place is a conversation about issues -- trade, immigration, education -- that appears downright respectful in tone.
"I cannot believe how civil it has been up here," Donald Trump said at one point.
That was after he said that he and his competitors on stage are "all in this together" when it comes to identifying solutions to the nation's problems.
It's a dramatic shift in tone that appears led by Trump and Marco Rubio, who in recent weeks have been engaged in an epic insult war.
Several days ago, Rubio acknowledged that his wife and children didn't like the way he was behaving. Trump, eager to appear presidential as he pivots to the general election, has also been quite consciously toning down his rhetoric.
And in typical Trump style, he is doing it in a way that is none-too-subtle. Hence his pause to look at the camera and remark on the civility of the debate.
Donald Trump might be right that the Republican Party's presidential primary is one of the "biggest political events anywhere in the world."
But are Democrats coming out in numbers as he claimed to vote for Republicans, namely, him?
The data are not yet as conclusive.
Yes, there has been record GOP turnout in early voting states Georgia and Kansas.
But party-flippers are not so clearly measured.
For example, in Massachusetts, nearly 20,000 Democrats changed their party affiliation before the state's primary, but most of them became independents, not Republicans.
In Pennsylvania, where voters go to the primary polls next month, 46,000 Democrats have switched.
Are they all voting for Trump? Maybe. "They’re voting out of love," he said.
But some might also be switching parties in order to vote against Trump.