US presidential primaries: Hillary Clinton, Donald Trump push to rebound in Northeast

The two candidates tried to build challenge-proof delegate majorities ahead of their nominating conventions against rivals Bernie Sanders and Ted Cruz

Front-runners Hillary Clinton and Donald Trump have pushed for big wins on friendlier terrain in the Northeast as they tried to build challenge-proof delegate majorities ahead of their nominating conventions against rivals who won't go away.

Both Trump and Clinton yesterday campaigned in New York ahead of its April 19 primary which offers a large trove of delegates who will select the parties' nominees at their national conventions in July.

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Trump is seeking to rebound in his home state after a decisive loss to his main rival, the ultraconservative Texas Sen Ted Cruz, last Tuesday in Wisconsin.

The billionaire real estate developer remains well short of the 1,237 delegates he needs to clinch the Republican nomination. His campaign is now focusing on developing a delegate-centred strategy akin to the one that Cruz has pursued for months.

"A more traditional approach is needed and Donald Trump recognises that," Paul Manafort, Trump's new delegate chief, said yesterday on NBC's "Meet the Press."

Even so, Trump later in the day complained that the system is "corrupt" and "crooked" and said it's unfair that the person who wins the most votes may not be the nominee.

"What they're trying to do is subvert the movement with crooked shenanigans," Trump told a crowd of thousands gathered in a packed airport hangar in Rochester, New York. "We're supposed to be a democracy," he added.

If denied the Republican nomination, he went on to warn, "You're going to have a big problem, folks, because there are people who don't like what's going on."

Clinton, who lost Wyoming on Saturday night to Vermont Sen. Bernie Sanders, is trying to maintain her commanding lead among delegates no matter how many states Sanders wins or how much "momentum" he claims. Key to her drive is a victory in New York, which she represented in the US Senate. Sanders, who was born in Brooklyn, can claim New York as his home state.

After stops in New York City churches, Clinton headed to Baltimore for her first campaign rally in Maryland, where she picked up the endorsement of popular local congressman Elijah Cummings.

Maryland, where Clinton is favoured, holds its primary on April 26 along with Pennsylvania, Rhode Island, Delaware and Connecticut.

Clinton's campaign is looking for big wins across the Northeast, in an effort to gain what they've termed an "all but insurmountable" lead in the delegate race.