WASHINGTON (CBSNewYork/AP) — Donald Trump has strengthened his grip on the Republican primary race and pushed tantalizingly close to a general election showdown with Hillary Clinton.

Trump earned 105 delegates Tuesday after winning all five primaries in Connecticut, Delaware, Pennsylvania, Maryland and Rhode Island.

The GOP front-runner is now about 400 delegates ahead of Ted Cruz, his closest Republican competitor.

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While Trump does need to keep winning in order to stay on his narrow path to the GOP nomination, he declared himself the party’s “presumptive nominee” after Tuesday’s results rolled in.

“I use the analogy of the boxer, you know, when the boxer knocks out the other boxer, you don’t have to wait for a decision,” Trump said.

On Wednesday, Trump fired shots at Clinton, accusing the Democratic front runner of using her gender to win votes.

“She is a woman. She is playing the woman card left and right,” Trump said. “She’s playing it much harder this time. And, she will be called on it.”

Clinton was quick with firing back at Trump’s claim.

“Mr. Trump accused me of playing the, quote, woman card,” Clinton said. “Well, if fighting for women’s health care and paid family leave and equal pay is playing the woman card, then deal me in.”

The Republican race now turns to Indiana, where next week’s primary marks one of Cruz’s last chances to slow Trump and push the race toward a contested convention.

This afternoon, Cruz is expected to make what he’s calling a “major announcement” about his campaign.

“I got good news for you,” Cruz told supporters Tuesday night. “Tonight, this campaign moves back to more favorable terrain.”

After Trump’s win, it’s impossible for the Texas senator to win the Republican nomination without a contested convention.

“Washington and New York want this general election to be between two rich liberal New Yorkers who believe on virtually every issue,” Cruz said. “That’s called ‘heads I win, tails, you lose.'”

There are 502 Republican delegates still at stake. John Kasich, who is trailing far behind both Trump and Cruz, has stopped campaigning in the Hoosier state all together.

“I’m not gonna be campaigning in Indiana,” he said. “Voters can figure out what they want to do.”

Over the weekend, Cruz and Kasich made an unconventional pact to slow the billionaire’s momentum. Both campaigns said Cruz will focus his resources on winning enough delegates in Indiana, while Kasich will focus his efforts on western states, including Oregon and New Mexico.

Trump needs to win 45 percent of the remaining delegates to officially be declared the Republican nominee. He was headed to Indiana Wednesday after delivering a foreign policy speech in Washington.

On the Democratic side, Clinton is now 90 percent of the way to her party’s nomination after four solid victories of her own Tuesday, including Pennsylvania which had 189 delegates up for grabs.

“With your help, we’re gonna come back to Philadelphia for the Democratic National Convention with the most votes and the most pledged delegates,” she told supporters.

Rival Bernie Sanders won Rhode Island, but is now lagging even farther behind in the delegate count. He still insists he’s more electable, vowing to stay in the race until the convention.

Sanders would need to win 80 percent

“Our national polls, which have us 15, 20 points ahead of Donald Trump, far more than Secretary Clinton,” he told supporters.

Sanders would need to win 80 percent of the remaining delegates to win the nomination.

Ninety-two delegates are up for grabs for the Democrats in Indiana’s primary, with 57 delegates available on the Republican side.

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