As Republicans in five states selected a presidential nominee Tuesday, frontrunner Donald Trump was victorious in Florida, North Carolina and Illinois while John Kasich pulled off his first win of the cycle in his home state of Ohio.

Meanwhile, Trump has the lead over [crscore]Ted Cruz[/crscore] in Missouri, which has not been officially called. Earlier Tuesday, Trump won nine delegates at the Northern Mariana Islands caucuses.

Trump’s Florida victory, winning 99 delegates, was a fatal blow to the campaign of Florida Sen. [crscore]Marco Rubio[/crscore], who announced his withdrawal from the race during a speech to supporters in Miami.

But Kasich winning Ohio’s 66 delegates could make it harder for Trump to win the necessary 1,237 delegates to secure the party’s nomination before the Republican National Convention this summer. His campaign says they expect a contested convention.

“We’re going to go all the way to Cleveland and secure the Republican nomination,” Kasich said at his election night celebration.

In a memo released after Ohio was called, Kasich’s chief strategist, John Weaver, argued “no candidate will win 1237 delegates.” He went on to say that “with the electoral map shifting significantly in our favor, Gov. Kasich is positioned to accumulate a large share of the almost 1,000 remaining delegates and enter Cleveland in strong position to become the nominee.”

Still, commentators said they see the contest turning into a two-man race.

“It’s between Cruz and Trump,” syndicated columnist Charles Krauthammer said on Fox News.

Likewise, Cruz said Tuesday evening: “Only two campaigns have a plausible path to the nomination.”

Speaking to supporters Tuesday evening, Rubio said in his concession speech: “While it is not God’s plan that I be president in 2016 or maybe ever — and while today my campaign is suspended — the fact that I’ve even come this far is evidence of how special America really is.”

Rubio’s withdrawal wasn’t completely unexpected. Last week, the 44-year-old senator said: “I believe with all my heart that the winner of the Florida primary next Tuesday will be the nominee of the Republican Party.” What happens next for Rubio is not clear: he opted not to run for re-election to the U.S. Senate this year as he sought the presidency.

Rubio didn’t endorse anyone in his speech. But some backers, including former policy adviser Avik Roy, are encouraging his supporters to get behind Cruz: “It’s time for all Rubio supporters—and all conservatives—to unite around @TedCruz.”

Inside the Donald J. Trump Grand Ballroom at his Mar-A-Lago Club in Florida, Trump allowed his campaign manager, Corey Lewandowski, to stand prominently next to him on stage during his election night speech. That seemed like an intentional move to display his confidence in Lewandowski, the subject of recent external criticism and allegations in the press.

During his speech, Trump called for the party to unify behind him, mentioning his recent chats with the Republican leaders in Congress.

“Paul Ryan called me the other day, tremendous call,” Trump said. “I spoke with Mitch McConnell today. We had a great conversation. The fact is: we have to bring our party together. We have to bring it together.”

According to the Associated Press tracker, Trump leads with 661 delegates, followed by Cruz’s 406 delegates and Kasich’s 142 delegates.

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