SEX and the City actress Cynthia Nixon’s bid to win the Democratic nomination for New York Governor has resulted in a crushing defeat.

Incumbent Andrew Cuomo fought off a challenge from the left and performed well across the state.

With roughly 60 per cent of the vote counted, Mr Cuomo had a lead of 66 per cent to 34 per cent for Ms Nixon as of 10:20pm local time (12.20pm AEST).

A minute after voting ended at 9pm (11am AEST), Ms Nixon released a statement essentially conceding and declaring that since polls showed Cuomo up by as much as 41 points, a narrower margin of victory could be seen as “a major embarrassment and significant underperformance for the two-term incumbent.”

Andrew Cuomo was a no-show at his own election night victory party and instead celebrated at the governor’s mansion in Albany, almost three hours from New York City.

It’s a highly unusual move for a winning candidate, but a spokeswoman said he chose to be with family.

The election result came after one of New York Governor Andrew Cuomo’s closest advisers was linked to a flyer accusing Nixon of being anti-semitic.

The revelations come five days since the flyer — paid by the state Democratic Party — hit 7000 mailboxes in Jewish neighbourhoods.

Mr Cuomo has adamantly denied he had anything to do with the smear.

But the New York Post reports that sources said one of his longtime confidants, Larry Schwartz, was deeply involved.

“Schwartz was very involved with the mailer and signed off on it,” a Democratic source said, describing the aide as a “henchman” and “enforcer.”

The source added: “It obviously blew up.”

The Cuomo campaign released a statement largely confirming the New York Post’s reporting.

“Larry Schwartz who serves on our campaign in a volunteer capacity was reviewing mail pieces in an ad hoc fashion, but he only saw the positive section of the mailer and never saw the negative section,” said Gov. Cuomo campaign spokeswoman Lis Smith.

“Had he seen it, it would have never gone out.”

“With anti-Semitism and bigotry on the rise, we can’t take a chance with inexperienced Cynthia Nixon,” reads the flyer.

Teachers’ union head Randi Weingarten, and her wife, Rabbi Sharon Kleinbaum — whose LGBT-friendly synagogue, Congregation Beth Simhat Torah, Nixon attends — issued a joint Facebook posting calling the mailing “beyond the pale.”

“How dare you, @nydems?!” tweeted NYC Council Member Brad Lander.

“Smearing @CynthiaNixon (whose kids are being raised Jewish, BTW) as soft on anti-Semitism & lying about her position on Israel in order to fearmonger and shill for votes is a shameful dead-end for our party,” he tweeted.

Sources told the Post that if Mr Schwartz was involved then Mr Cuomo would have known.

“We all know that Larry is the person closest to the governor and he doesn’t do anything without the Cuomo’s knowledge,” said a transit source. “It’s similar to a criminal cartel where they only communicate verbally to a handful of trusted people, of which Larry is one.”

Ms Nixon has demanded the Democratic Party denounce Mr Cuomo after the “smear” job.

Nixon, who played lawyer Miranda Hobbs from 1998 until 2004, is a long way behind in the polls as New Yorkers go to the polls today.

A recent Siena College poll had Gov. Cuomo at 63 per cent, Nixon a long way back at 22 per cent with 15 per cent still undecided.

The Cuomo campaign named a longtime staffer, David Lobl, as the actual author of the flyer.

However, Democratic sources told the Post that Mr Lobl was tasked with digging into allegations that Nixon was anti-Semitic, but ultimately disproved them.

Mr Lobl is the “fall guy,” said a source. “The real story is the campaign did this.”

Two other sources confirmed that Mr Lobl — who spent nearly six years as a “Special Assistant to the Governor” — was formerly in charge of outreach to New York’s politically important Jewish communities.

While he left Gov. Cuomo’s office in May to join a lobbying firm, he remains linked to Cuomo-world.

“He’s still going to campaign meetings,” a well-placed Democrat confirmed.