Here's the latest news, and below are the full Republican primary election results:
The Latest News
ABC News projects Trump will win the Florida GOP primary, based on analysis of the vote.
Florida was a key state for Rubio to win in order to sustain his hopes of being the Republican nominee. The Florida senator was adamant all along that he would win, but ultimately it was Trump who came out victorious in Rubio’s home state and Rubio suspended his campaign.
"This is my second home, Florida, to win by that kind of a number is incredible," Trump said at his press conference in Palm Beach, Florida. "And I have to say that number one I want to congratulate Marco Rubio on having run a really tough campaign. He's tough, he's smart and he's got a great future."
Trump won across ideology, income, education, and partisan groups, according to preliminary exit polls. He won among voters 30 and older.
The real estate mogul also fared well among evangelicals and non-evangelicals alike.
Rubio did however beat Trump among a few groups -- nine percent of voters of Cuban descent, voters focused on experience versus an outsider and voters who prefer someone who shares their values.
ABC News projects Trump will win the Illinois Republican primary, based on analysis of the vote.
Preliminary exit poll results showed that Illinois Republicans see eye to eye with Trump on his signatures issues like deporting immigrants and banning Muslims from entering the U.S.
Very conservative voters showed up for Sen. Ted Cruz, giving him just over half of their votes, but Trump beat Cruz among somewhat conservatives and moderates.
However, a third of Illinois Republicans said they definitely wouldn’t support Trump were he the nominee – more than in any other state.
The last time Trump was in the Land of Lincoln, he postponed his campaign rally at the University of Illinois at Chicago over what his campaign cited as security concerns.
Following the announcement, the scene turned into mayhem as Trump supporters and protesters clashed inside the pavilion and several arrests were made.
ABC News projects that the Missouri GOP primary is too close to project.
With 94 percent of precincts reporting in Missouri, Trump and Cruz are separated by .3 of a point in the Republican primary.
ABC News projects Trump will win the North Carolina GOP primary, based on analysis of the vote.
Trump had Cruz on his tail in the North Carolina contest.
Trump and Cruz split voters' top two attributes they look for in a candidate, preliminary exit poll results show. More than half of shared-values voters went for Cruz, while half of those seeking “needed change” for Trump.
They also split early versus late deciders. Trump won nearly half of those who decided more than a month ago -- while Cruz got nearly four in 10 of those who decided in the past month.
Somewhat conservatives picked Trump over Cruz 43-30 percent, and moderates and liberals also went for Trump over Cruz, 38-22.
Cruz also beat Trump among younger voters and college graduates. But Trump won evangelicals, though by a slim margin.
More than half of North Carolina voters said they preferred an outsider over someone with political experience, and Trump won two-thirds of these voters.
ABC News projects Kasich will win the Ohio Republican primary, based on analysis of the vote.
The Ohio governor certainly has something to celebrate -- a win in his home state.
The victory provides momentum to a candidate who was trailing far behind in delegates and who had yet to win a primary.
For more than a third of voters, the economy was the top issue for them and a majority of them went for Kasich, according to exit poll results.
Kasich garnered a majority of voters with a college degree, while Trump won among those without one. Kasich also won every age group, beating Trump 47-26 percent among voters age 30 and under.
Non-evangelicals accounted for nearly half of Ohio GOP primary voters Tuesday and Kasich also benefited from their strong turnout.
Kasich appeared on stage at his election party, visibly happy and emotional, after learning of his win.
"Now, I want you to know the campaign goes on, and I also want you to know that it's been my intention to make you proud," Kasich said to his supporters in Berea, Ohio.
Kasich continued: "...Even though I labored in obscurity for so long, people counting me out...But we put one foot in front of the other."
"I want to remind you, again tonight, that I will not take the low road to the highest office in the land," Kasich vowed.
ABC News' Analysis Desk contributed to this report.