Is the race for the White House now down to two?
Trump and Clinton left opponents in their dust in New York, romping to victories in the latest primary.
The northeastern states are now in their sights, and then the final stand looms in California.
Trump's crushing victory over Ted Cruz in Tuesday's party nominating contests in New York tilted the energy in the Republican race back to the front-runner.
Clinton's win over Bernie Sanders, while narrower, broke a string of victories by the democratic socialist and gave her a much-needed lift.
Trump's win marked a rebound from his Wisconsin defeat two weeks ago and set him up for another big night on April 26, when Pennsylvania, Connecticut, Rhode Island, Delaware, and Maryland will hold primaries.
"Ted Cruz is mathematically out of winning the race," Trump said Wednesday on Twitter. "Now all he can do is be a spoiler, never a nice thing to do. I will beat Hillary!"
Trump, 69, predicted some "amazing weeks" ahead for his campaign.
If he and Clinton do go on to secure their respective parties' nomination for the November 8 election, opinion polls show Clinton with a sizeable lead.
Political commentator Josie Pagani told Paul Henry this morning there's no way Bernie Sanders will be able to win.
"The delegates still to win in the primaries and caucuses are predominantly favouring Clinton. Sanders is winning with white men. He can't mathematically win."
She said that Sanders was never in the race to win.
"Really he was going in with a message, he can't win and Hilary knows that."
Despite not having the numbers Clinton has, Trump is overwhelmingly in the lead.
He is ahead in all five states on the northeastern coast.
Ms Pagani said: "The problem for Trump will be in the flyover states, as they tend to favour Cruz. The Republican establishment will use Cruz to bump Trump from having that majority."
She says there's no way Cruz will win as the Republicans don't like him anymore than they like Trump.
Reuters / Newshub.