WASHINGTON — Donald Trump scored decisive victories in Michigan and Mississippi Tuesday night, delivering a stinging rebuke to well-financed critics trying to block his road to the GOP presidential nomination.

Trump easily carried Michigan — a Rust Belt prize that adds to his diverse collection of wins — after a campaign where he vowed to claw back lost US auto jobs from Mexico and Asia.

Ohio Gov. John Kasich, who has staked his candidacy on performing well in the Midwest, was fighting for second place with Texas Sen. Ted Cruz.

In Mississippi, networks declared Trump the winner within an hour after the polls closed.

Trump also won the caucuses in Hawaii.

Exit polls showed that nine out of 10 voters in both states were either “dissatisfied” or “angry” with Washington, which Trump has emphasized.

Cruz, however, was able to win in Idaho, where he routed Trump by 45-28 percent.

The big victories gave Trump a new burst of energy.

“Does Trump know how to close? Winning is winning,” Trump said at a press conference at his golf resort in Jupiter, Fla.

“I want to thank the special interests and the lobbyists, because they obviously did something to drive these numbers,” he added, taking a shot at rivals and establishment Republicans who have spent millions on ads attacking him.

Speaking before a bank of American flags, Trump declared it was time for Republicans to unite.

“We should grab each other and unify the party,” he said, hailing House Speaker Paul Ryan and pledging to get along with critics such as Mitt Romney.

Trump hauled out samples of a collection of his self-named products — Trump Wine, Trump Water and Trump Steaks — in defiance of those who have questioned his business acumen.

“If you want to take one, we’ll charge you about 50 bucks a steak,” he joked with reporters.

Florida Sen. Marco Rubio’s weak performance Tuesday night was tough medicine for a candidate who had been the hope of the establishment to upend Trump.

Rubio avoided any mention of the primaries in a speech to supporters in his home state of Florida, arguing that he still had a chance in the next round of major contests next Tuesday.

Here’s how the Republicans could steal Trump’s nomination: