Cuomo, who always led in the polls and outspent his rival more than 8 to 1, seldom mentioned Nixon by name during an often-nasty campaign, instead touting his experience, achievements in two terms as governor and his work to push back against President Donald Trump.
In his moment of victory, Cuomo was oddly silent, skipping his own election-night party in Manhattan to celebrate with family at the governor's mansion in Albany. He put out a tweet that said simply "Thank You New York." His campaign declined to issue a statement.
"It's New York's obligation to stand up and lead and lead against a lot of these changes in Washington that are totally opposite of who we are as New Yorkers and what we believe," he said earlier at his Westchester County polling place. "There is a divisiveness coming out of Washington that I think is cancerous to this nation."
Thursday's results were good across the board for Cuomo, whose preferred candidates for lieutenant governor and attorney general also survived contentious primaries. And despite Nixon's loss, liberals celebrated victories for several left-leaning challengers who ousted longtime legislative incumbents.
With registered Democrats outnumbering Republicans more than 2 to 1 in New York, Cuomo becomes the automatic front-runner in November's matchup with Republican Marc Molinaro and independent Mayor Stephanie Miner.
Nixon, a longtime education activist and actress best known for her Emmy-winning role as lawyer Miranda Hobbes on HBO's "Sex and the City," was counting on a boost from liberals looking to oust establishment politicians. She called herself a democratic socialist and pointed to recent congressional primary victories by New York's Alexandria Ocasio-Cortez and Massachusetts' Ayanna Pressley as evidence that underdog challengers can defy the odds.
When that didn't happen, Nixon thanked supporters and credited her campaign for helping to push Cuomo to the left and show that liberals have a shot at making big changes.
"Before we take our country back we have to take our party back," she said. "This is an incredible moment for progressives but it's not just a moment. It's a movement."
Cuomo, who won with about 65 percent of vote, secured endorsements from Hillary Clinton, Joe Biden and even Nicki Minaj, and spent much of the race touting his own liberal accomplishments such as same-sex marriage, gun control and paid family leave. And he increasingly made the race about pushing back against Trump and other Republicans. At the same time, he dismissed Nixon as a naive dilettante and mocked her work as an actress.
"If it was all about name recognition," he said earlier this year, "then I'm hoping Brad Pitt and Angelina Jolie and Billy Joel don't get into the race."
Despite the rhetoric, Cuomo took Nixon seriously, spending $8.5 million, largely on ads, in the final weeks of the campaign to answer attacks that he has not invested enough in New York City's beleaguered subway system and failed to deliver on upstate economic development promises.
There were indications that the 52-year-old Nixon's aggressive campaign pushed the incumbent governor to the left on several issues, including legalizing marijuana and addressing crumbling public housing in New York City.
"Cuomo is no idiot," said Fordham University political scientist Christina Greer. "The winds of change right now are with insurgent candidates and not necessarily with incumbents. ... He didn't just slightly pivot, he full-on leapt to the left."
While he may have won, Cuomo, a former U.S. housing secretary and son of the late Gov. Mario Cuomo, did not escape the primary unscathed.
During the campaign's only debate, Cuomo snuffed out speculation that he might run for president in 2020, pledging to serve a full four-year term if re-elected.
He was mocked for saying America "was never that great" during remarks criticizing Trump's "Make America Great Again" slogan.
He invited Clinton to a celebratory opening of the final span of the new Gov. Mario M. Cuomo Bridge over the Hudson - only to keep the bridge closed after engineers warned that pieces from the old, largely disassembled Tappan Zee Bridge could hit the new structure.
Cuomo claimed to have no knowledge of a Democratic Party mailer that questioned Nixon's support for Jewish people - despite Cuomo's control of the party and a recent $2.5 million contribution to its campaign operations. Cuomo's spokeswoman later acknowledged that two former aides volunteering on the campaign were behind the piece.
Nixon, who is raising two of her children in the Jewish faith, demanded an apology that never came.
In the Democratic primary for lieutenant governor, incumbent Kathy Hochul, a former congresswoman from Buffalo, defeated challenger Jumaane Williams, a New York City councilman who had promised if elected to serve as a check on Cuomo.
Cuomo's pick for attorney general, New York City Public Advocate Tish James, won a four-way Democratic primary.
Nixon now must decide whether she wants to run on the November ballot as a candidate for the third-party Working Families Party, thanks to a New York state law that allows candidates to run on multiple ballot lines. Early in the campaign, Nixon said she would stand aside if she lost the Democratic primary, but it remains to be seen whether the party can remove her name from the ballot.
Associated Press writers Stephen R. Groves and Sabrina Caserta contributed this report.
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