Neither Cuomo nor Nixon made any immediate public comment after US media called the race.

Lower down the ticket, the candidate Nixon endorsed as lieutenant governor, Jumaane Williams, a 42-year-old city councilman from Brooklyn, was narrowly ahead of incumbent Kathy Hochul in a race that was considered too close to call by US media.

“He is an experienced man and she is totally inexperienced,” explained Cuomo voter Jack Buchanan, 87, on Manhattan’s Upper East Side.

“We already have a totally inexperienced guy in the White House, so why put one in Albany?” he added in reference to the state capital and President Donald Trump, who is hugely unpopular in the city.

“I don’t think she’s qualified,” Nixon voter Jill Vexler said in Union Square, confessing it had been “more of a sympathy vote.”

“I don’t think she has enough strategy to get the money to do what she wants to do, but I do like what she wants to do.”

Nixon had hoped to ride the crest of other upset victories by political first-timers in Democratic Party primaries for congressional seats in places like New York and Boston.

The public school advocate and LGBT activist campaigned hard for universal health care, rent controls and fixing the decrepit subway.

Yet she headed into Thursday’s vote trailing Cuomo in every single demographic group, the governor leading 63-22 per cent, up from 60-29 per cent in late July, according to the last poll from Siena College.

Winning statewide is a much tougher gambit than a congressional seat, especially for a first-timer up against the well-oiled and well-funded machinery of a sitting governor.

“To break through, that requires a lot of money and organisation,” said Michael Miller, professor of political science at Barnard College. “A lot of people would be surprised if she did pull it off,” he said

Cuomo, the son of a governor who married a daughter of Robert F. Kennedy and had three children before they divorced, traded hard on his record on gun control, gay marriage and the minimum wage.

Said to harbour presidential ambitions, he is a long-time political operator who served as a cabinet secretary under Bill Clinton at the tender age of 39.

“Andrew Cuomo has outspent us 10 to one which says to me that he is really scared,” Nixon told supporters in Union Square earlier on Thursday, where queues formed to take a picture with her.

“Our voters are really pumped to get out and vote today and to get everybody they know out to vote, and in the end that’s what counts.”

The final home stretch of the race degenerated into ugly spats. She denounced as a smear campaign a Democratic Party mailer that implied she was anti-Semitic, to which Cuomo pleaded ignorance.

Then she sailed into controversy and free column inches of her own with a bagel order that incensed almost everyone, an incongruous lox, cream cheese, tomatoes and capers – on a cinnamon and raisin bun.