Donald Trump swept all five presidential primaries held on Tuesday, strengthening his grip on the Republican party race for a US presidential nomination, while Democrat Hillary Clinton raced ahead of rival Bernie Sanders.

Trump demolished Ted Cruz and John Kasich in Connecticut, Delaware, Maryland, Pennsylvania and Rhode Island - a stunning show of force by a candidate seen as a populist political saviour by millions despite being loathed by the party establishment.

Trump's campaign "is moving slightly to the centre" in order to appease the Republican establishment, political strategist Morris Reid told Al Jazeera.


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"Once he secures the numbers, I think you'll see him nose dive to the centre," Reid said. 

"I consider myself the presumptive nominee," the real estate mogul told a crowd at Trump Tower in New York, despite still being short of the 1,237 delegates required to win the nomination outright.

"As far as I'm concerned, it's over."

Democratic frontrunner Hillary Clinton won in four states: Connecticut, Maryland, Delaware and Pennsylvania.

Trump and Clinton were expected to do well in Tuesday's five contests, which also included Rhode Island where Democrat rival Bernie Sanders won.


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Sanders' team has sent mixed signals about his standing in the race, with one top adviser suggesting a tough night would push the Vermont senator to reassess his bid and another vowing to fight "all the way to the convention" in July.

"Despite outspending Clinton in political ads in all five states, Sanders couldn't overcome Clinton's wall of institutional support within the Democratic party," Al Jazeera's Kimberly Halkett reported from Baltimore.

Clinton was already looking past Sanders, barely mentioning him during recent campaign events.

"What a great night," the Democratic frontrunner told a crowd of supporters in Philadelphia, Pennsylvania.

"Let's go forward, let's win the nomination, and in July let's return as a unified party," she said.

Trump's huge night

The 68-year-old former secretary of state, however, deepened her attacks on Trump, casting the billionaire businessman as out of touch with Americans.

"If you want to be president of the United States, you've got to get familiar with the United States," Clinton said.

"Don't just fly that big jet in and land it and go make a big speech and insult everybody you can think of."


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Trump's night was nothing short of huge, as he cleared 50 percent support in all five states, with nearly all precincts reporting. In Rhode Island, he earned 64 percent, trouncing Kasich (24 percent) and Cruz (10 percent).

Most importantly, the bombastic 69-year-old extended his lead in the all-important race for delegates who will officially choose the Republican nominee at the party's convention in July.

"Ted Cruz realises that his brand of conservative Republicanism doesn't play particularly well in the northeast part of the country," Al Jazeera’s Alan Fisher, reporting from Philadelphia, Pennsylvania.

Trump's triumph comes in the heated aftermath of the revelation that Cruz and Kasich, desperate to prevent the frontrunner from securing the nomination, were teaming up to block him in future races.

"Within 72 hours of this pact being announced, Kasich said he wouldn't recommend to his supporters not to vote for him in Indiana. That was really just manna from heaven as far as Donald Trump was concerned, a real propaganda victory... saying that politicians can make promises but they can't get anything done," Fisher said.

Source: Al Jazeera and agencies