By Associated Press

NEW YORK — Republican Donald Trump emerged from Wisconsin as a damaged front-runner following a crushing loss to rival Ted Cruz, deepening questions about the billionaire businessman’s presidential qualifications and pushing the GOP toward a rare contested convention fight.

Both parties are turning their sights toward New York, which offers a massive delegate prize in its April 19 contests.

Trump, who has dominated the Republican race, suddenly finds himself on the defensive as the campaign moves east. He’s struggled through a series of missteps, including his campaign manager’s legal issues after an altercation with a female reporter and his own awkward explanation of his position on abortion.

Exit polls in Wisconsin highlighted the deep worries about Trump surging through some corners of the Republican Party. A majority of GOP voters said they’re either concerned about or scared of a potential Trump presidency, according to surveys conducted by Edison Research for The Associated Press and television networks.

Cruz has stepped forward as the candidate best positioned to block Trump, though it would likely take a convention battle to accomplish that goal. A Texas senator with a complicated relationship with Republican leaders, Cruz cast his Wisconsin victory as a “turning point” in the race.

“We’ve got the full spectrum of the Republican Party coming together and uniting behind this campaign,” he said.

Trump was unbowed in his defeat. His campaign put out a biting statement accusing Cruz of being “worse than a puppet — he is a Trojan horse, being used by the party bosses attempting to steal the nomination from Mr. Trump.”

Trump still has a narrow path to claim the nomination by the end of the primaries on June 7. But by losing Wisconsin, the real estate mogul has little room for error in upcoming contests.