Republican candidate Donald Trump scored more big victories in his bid to be the party's presidential nominee, winning the key state of Florida and knocking home-state senator Marco Rubio out of the race.
Hillary Clinton surged ahead in the Democratic presidential race, winning four states that voted in the latest round of one-day multi-state nominating contests. Her victories almost guarantee that she will be the Democratic nominee in November's White House election.
Mr Trump won three of Tuesday's five state contests, strengthening his grip on the Republican race, but he lost Ohio to the state's governor John Kasich, preventing a clean sweep for the businessman.
The state loss for Mr Trump raises doubts about whether he will secure the 1,237 delegates he requires to lock down the nomination.
At the very least, the latest results show that the Republican race will likely run all the way until the primary ballots end on June 7th.
Mrs Clinton showed that the recent victory by her rival Bernie Sanders, the Vermont senator, in Michigan was something of an anomaly as she took the industrial states of Ohio and Illinois, where she was born, and North Carolina along with a landslide victory in Florida.
She held a slight lead in Missouri, the last race to be counted on the night, by 49.6 to 49.4 per cent, with almost all of the votes counted.
Status
Mr Trump added his Florida win to victories in Illinois and North Carolina, solidifying his status as the lead Republican candidate.
He was ahead of his chief rival Texas senator Ted Cruz, who will likely benefit from Mr Rubio's departure, by a thin margin in Missouri.
In a humiliating defeat, Mr Rubio, the 44-year-old Cuban American senator with a plan to create a “new American century” lost out to the brash businessman who had ridiculed him as “Little Marco”.
The first-term senator said that “while it is not God’s plan that I be president in 2016, or maybe ever,” he asked that the American people do not give into fear or frustration, in remarks directed at Mr Trump.
“We can disagree about public policy, we can disagree vibrantly and passionately, but we are a hopeful people,” he told his supporters in his concession speech in Florida.
Mr Trump picked up all of that state’s 99 delegates in a winner-takes-all contest, beating Mr Rubio convincingly by 46 per cent to 27 per cent.
Without naming the tycoon, Mr Rubio urged Americans not to succumb to the angry rhetoric that has dominated the Republican race.
“The politics of resentment against other people will not just leave us a fractured party,” he said. “They’re going to leave us a fractured nation.”
The New York property magnate struck a rare conciliatory tone at his victory party at his Mar-a-Lago Atlantic coastal resort congratulating Mr Rubio on “a really tough campaign”.
“He’s tough, he’s smart and he’s got a great future,” he said.
Delegates
Mr Trump passed the half-way mark in the path to the 1,237 delegates he needs to win. He added 178 delegates, bringing his total to 640, followed by Mr Cruz with 408 and Mr Kasich with 138.
The businessman’s 11-point loss in Ohio raises the possibility that the Republican establishment, fearful of Mr Trump’s chances in the November ballot, may be able to sway the contest over the presidential nomination at the Republican national convention in July.
Mr Kasich's strategy will be to use the momentum from his sole victory in the Republican race to perform well in states such as Pennsylvania, where he was born, and other Midwestern states.
Although he, like the frontrunner, may not reach the 1,237 magic number in terms of delegates, he will aim to head into a potential contested convention in Cleveland in July as the strongest candidate.
Mr Trump, who has 18 state wins to Mr Cruz’s eight, needs to win three in every five of the remaining delegates at stake to secure the nomination, which, despite his performances, may be a goal too far.
Despite at least four state losses on the night, Mr Sanders refused to concede defeat, even though calculations show that it is almost impossible for him to close the gap on Mrs Clinton’s delegate lead.
“With more than half the delegates yet to be chosen and a calendar that favours us in the weeks and months to come, we remain confident that our campaign is on a path to win the nomination,” he said.
The former secretary of state increased her delegate lead over the democratic socialist, once considered a long-shot candidate, to more than 300 delegates, excluding the large number of “super-delegate” elected officials and party leaders whose support she has secured.
Mrs Clinton won at least 297 delegates in Tuesday’s state ballots and Mr Sanders 194, bringing their respective totals to 1,069 and 768. Her super-delegate supporters push Mrs Clinton’s total to 1,541.
Appeal
Tuesday's victories confirmed that she has the broadest appeal of the support base of the Democratic Party, winning over Hispanic and African American voters and blue, white collar voters in Ohio.
“We are moving closer to winning the Democratic Party nomination and winning this election in November,” she said.
Mr Trump, also with an eye on the November ballot, urged Republicans to unite behind him.
"We have something happening that actually makes the Republican Party the biggest political story anywhere in the world," he said, pointing to "millions" of new voters he is drawing to the party.
“Democrats are coming in, independents are coming and very, very importantly, people that never voted before,” he said.
“It’s an incredible thing.”
