Does Trump have the nomination sewn up?

Republican presidential candidate Donald Trump speaks during a campaign stop in Indianapolis. Photo / AP

The Empire State building, a few streets from where he stood, was turned red in his honour.

Trump Tower was bathed in red, white and blue. The Stars and Stripes hung in the centre of the rose marble and gold atrium. And a man not known for his understatement made a claim about his presidential election campaign which was bold, even for his standards.

"We are going to get more delegates than anyone projected in their wildest imagination," said Donald Trump, crowing about his New York primary victory.

"We don't seem to have much of a race any more," he said, adding that his campaign was "really rocking."

Victory in his home state was no surprise, although it has certainly given him a spring in his step. But just how "rocking" is his campaign? And does this now mean he has it sewn up?

To win the Republican nomination, a candidate needs to claim 1237 delegates. If any of the three remaining candidates fail to clinch 1237 then the party will have a contested convention - which could produce a wildly unpredictable result. Journalists are rubbing their hands in glee at the anticipation of such drama; party grandees are tearing their hair.

Before yesterday's contest, Trump led the Republican race with 756 delegates, ahead of Senator Ted Cruz with 559 and Ohio Governor John Kasich with 144.

Trump picked up 89 of New York's 95 delegates, putting him on a narrow path to clinch the nomination by the end of the primaries - if he keeps winning.
Kasich won four delegates and Cruz was shut out.

The last two delegates will have to wait until the absentee votes are counted.

Trump has won 47 per cent of the delegates awarded so far. He has to win 57 per cent of the remaining delegates to clinch the nomination and avoid a contested convention.

He now has 845 delegates. His job will still be hard, but it's possible.

Given the complexities of delegate allocations in each state, Trump still would have just a tiny margin for error in the final seven weeks of the primaries.

He will be happy to have won in New York, although not particularly surprised.
"It's really nice, I have to say, that the people who know me the best, the people of New York, give me this kind of vote," he said.

"I can think of nowhere that I would rather have this victory," he said, emerging to the podium to the strains of Frank Sinatra's New York, New York.

"Nobody is going to mess with us - that I can tell you."

Nobody except, perhaps, his own party.