Ms. Nixon's campaign has been heavily outspent by Mr. Cuomo, and has been banking on the long-shot appeal of insurgents this year, citing the victories of candidates like Alexandria Osasio-Cortez, who beat a longtime incumbent, Representative Joseph Crowley, in a Democratic primary in June.
His campaign spent about $400,000 per day during a recent three-week stretch, only slightly less than Nixon's total outlay over the same period. I have no authority in the situation at all, I can't say do this or do that.
Cuomo's lead is up from 60 percent to 29 percent a Siena poll recorded at the end of July.
In an interview Saturday morning, Nixon argued that corruption in Albany, the state capital, can only be cleaned up, and the struggles of working-class New Yorkers properly addressed, by someone from outside the halls of power - someone like her.
Nixon, who has two children being raised in the Jewish faith, called the mailer "dirty, sleazy politics" and said Cuomo's explanation that he didn't know about the mailer isn't believable.
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The storm was edging closer to the USA and was 975 miles (1570km) east-south-east of Cape Fear, North Carolina. North Carolina, South Carolina and Georgia coasts could experience prolonged hurricane-force winds and rain.
The mailer was sent by the state party, which Cuomo controls, and comes days before Thursday's primary for governor. Sent ahead of the Jewish High Holidays, the mailer falsely claimed that Nixon supported the campaign to boycott Israel, and that she has refused to fund yeshivas if elected.
Nixon said the race is much closer than the polls indicate, adding that Cuomo wouldn't be spending so much money against her if the race wasn't close.
"It seems very clear that the bridge was not ready to open", Nixon said Sunday. "And when I'm governor, she will be". But he claims he knew nothing about the mailer and did not approve it.
Party director Geoff Berman now says the mailer was "wrong and inappropriate".
Flanked by Rabbi Barat Ellman and other supporters, Nixon noted, "As a mother of Jewish children whose grandparents barely escaped the Holocaust and had lots of relatives who did not, this is a truly shameful thing to be accusing my family of, particularly at a time when anti-semitism is really on the rise in this country".