WASHINGTON — The Latest on the 2016 presidential race as Republicans look back on South Carolina's primary and ahead to Nevada's caucuses on Tuesday and Democrats move past their Nevada contest and await a South Carolina faceoff on Saturday:

Donald Trump's rivals are running out of time to stop him.

After Saturday's dominant performance in South Carolina, a close look at the calendar of upcoming elections suggests the New York billionaire's rivals have until mid-March to slow him down.

After that, their only chance to keep Trump from representing the Republican Party in the general election may be a nasty, public fight at the GOP's national convention.

The reason is delegates — and how they're awarded in the Republican Party.

While winning states generates headlines, a candidate wins the party's nomination by collecting a majority of the delegates awarded in presidential primaries and caucuses.

This year, most Republican contests award delegates proportionally, based on each candidate's share of the vote. That could make it hard for Trump to build a big lead, because even the second- and third-place finisher can win delegates.

But if one candidate is able to run up a significant lead — as Trump has begun to — proportional contests also make it difficult for others to catch up.

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Bernie Sanders says in South Carolina that the economy is "a lot better" than it was seven years ago "thanks to President Obama."

Sanders made an unannounced stop at a luncheon following services at a Baptist church in West Columbia, South Carolina. He says he would work to fix a "broken criminal justice system" and give black Americans more economic opportunities.

Sanders spoke the mostly black audience ahead of next Saturday's South Carolina primary, where polls show him trailing Hillary Clinton by wide margins among African Americans who make up more than half of the electorate in state primaries.

Clinton has questioned Sanders' loyalties to Obama, the nation's first black president.

Sanders is holding a rally later in the day in Greenville, South Carolina.

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The election calendar may have Democrats voting next in South Carolina, but Hillary Clinton and Bernie Sanders already have their eyes on bigger prizes to come in March.

That's the month that will likely determine whether the Vermont senator can keep pace in the party's White House race.

Clinton shook off some of the anxieties shadowing her campaign with a solid victory in Saturday's Nevada caucuses.

More than half of the 2,383 delegates needed to win the Democratic nomination will be determined in the 28 states that hold primaries and caucuses in March.

While Clinton and Sanders should have enough money to stay in the race for weeks afterward, the delegate tally at the end of the month could make the result inevitable.

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Sen. Dean Heller says he's endorsing GOP presidential contender Marco Rubio.

The Nevada senator's support could be critical to Rubio's fortunes in the state two days before the GOP caucus.

Heller says in a statement that Rubio is "the candidate capable of uniting conservatives, growing our party, and beating the Democrats in November."

Rubio is hoping his second-place win in South Carolina Saturday makes him a viable alternative to establishment Republicans turned off by front runner Donald Trump.

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Hillary Clinton says Donald Trump and Ted Cruz "missed the mark" when they described their posture toward the Israeli-Palestinian conflict.

Trump has recently suggested that he'll be "sort of a neutral guy" in the dispute. Cruz, meanwhile, says he has, "no intention of being neutral" in his support for Israel.

The former secretary of state suggested on CNN's "State of the Union" that the situation is far more complex. She pledged to defend and do everything she can to support Israel, but adds, that "the Palestinians deserve to have a state of their own. That's why I support a two-state solution."

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Donald Trump is leading the delegate count in the Republican presidential nomination.

The billionaire businessman hauled in all of South Carolina's 50 delegates in Saturday's primary, giving him a total of 67. Sen. Ted Cruz has 11 delegates and Sen. Marco Rubio has 10.

The South Carolina results marked a major disappointment for Cruz, whose path to the nomination requires strong performances across the South. The Texas senator finished well behind Trump in the state known as the gateway to the South — despite Cruz's appeal among evangelical Christians and his southern roots.

Based on the way the state's delegates are apportioned, neither Cruz nor Rubio won any in what is shaping up as a three candidate race.

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Note to Marco Rubio, Ted Cruz, Donald Trump and anyone else who wants John Kasich to exit the race for the GOP presidential nomination: Not gonna do it. Not anytime soon, at least.

The Ohio governor tells CBS's Face the Nation that for him, the goal is gathering delegates in such Republican contests as Massachusetts, Vermont, Virginia, Mississippi, Michigan and Illinois. He says, "I don't have to win in these places, I just have to hang in there and continue to gather momentum."

Kasich argues that besides, he's the only governor left in the GOP field, now that former Florida governor Jeb Bush has exited.

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Trump acknowledges he probably needs to act more presidential and says he'll do so "pretty soon."

The often brash Trump tells Fox News Sunday, "I think I'll be very presidential at the appropriate time. Right now, I'm fighting for my life."

Trump has chalked up his second win in a row, duplicating his success in New Hampshire with a win in South Carolina on Saturday. His victory comes after a week in which he threatened to sue one rival, accused former President George W. Bush of lying about the Iraq war and even tussled with Pope Francis on immigration.

Trump says he "can act as presidential as anybody that's ever been president other than the great Abraham Lincoln." He says Lincoln was hard to beat.

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Cruz says that his third place finish in South Carolina is effectively a tie for second place with Rubio.

The Associated Press has called the race for Trump, with Rubio placing second by two-tenths of 1 percentage point over Cruz, who finished third.

Cruz said Sunday on ABC's This Week that, "last night we effectively tied for second," adding that, "there is now only one strong conservative remaining in this race who can win.

Cruz says the "game plan from Day One was to do well in the first four states and consolidate conservatives to go forward to Super Tuesday" on March 1. "We're positioned ideally to do exactly that."

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Democratic presidential candidate Bernie Sanders says his loss to Hillary Clinton in Nevada probably was caused by lower voter turnout.

The Vermont senator says on NBC's Meet the Press Sunday that "We will do well when young people, when working-class people come out" to vote. He adds: "We did not do as good a job as I had wanted to bring out a large turnout."

The state party estimates that 80,000 Democrats caucused Saturday. That's about 10,000 more than most expected but still well below the nearly 120,000 who showed up in 2008.

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The national Republican chairman says the party is ready "for anything" at the nominating convention in July.

Reince Priebus is talking about a scenario where no presidential candidate comes to the GOP convention this summer with the necessary number of delegates from the primary campaign to clinch the nomination on the first ballot.

He tells ABC's This Week that "we will be prepared if that happens, but again I don't think that's going to be the case.

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Hillary Rodham Clinton says she understands that independent voters in particular have questions about whether they can trust her.

She says on CNN's State of the Union that voters have an "underlying question...is she in it for us or is she in it for herself?"

She adds: "That's a question that people are trying to sort through...I know that I have to make my case."

The FBI is investigating whether classified information passed through Clinton's homebrew server while she was secretary of state.

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Trump is rejecting the idea that the Republican nomination is his to lose after his big win in South Carolina.

Trump says on CBS' Face the Nation that he still faces some tough competition, so "I don't want to say it's mine."

Trump was asked about Marco Rubio's suggestion that he needs to be more specific about his policy ideas. The billionaire businessman responded that he has "great knowledge of foreign policy." And he says he's a better vision for how to end the bloodshed and unrest in Syria than those who offer themselves as "great military geniuses."

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Rubio says he's in good shape to more directly take on Trump as a smaller Republican field moves on after South Carolina.

The Florida senator tells CBS' Face the Nation that the choice for Republicans is becoming "clearer and clearer" now that rival Jeb Bush is out of the race.

Rubio says it's time for Trump — who won in South Carolina on Saturday — to start spelling out clear policy positions on national security matters, health care and more.

Rubio puts it this way: "If you're running to be president, you can't just tell people you're going to make America great again."

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Fresh from his victory in South Carolina's primary, Republican presidential candidate Donald Trump is sending a big thank you to Sarah Palin.

In a tweet, Trump is citing the former Alaska governor and 2008 vice presidential nominee for her "amazing help and support." Palin has endorsed the billionaire businessman in the GOP race.

Trump says he had a big win on Saturday and that "the people of South Carolina got it."

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The presidential candidates are on the move.

On the Republican side, Donald Trump is looking for support in Atlanta on Sunday. Marco Rubio plans stops in Tennessee and Arkansas before ending up in Nevada. That's where you'll find Ted Cruz — ahead of Tuesday's caucuses there.

Democrat Bernie Sanders campaign in the South — South Carolina, which holds its party primary this coming Saturday. Hillary Clinton is supposed to be fundraising in California.