Going into the last weekend before the Democratic primary, Governor Andrew Cuomo was riding high, capping off a packed week of well-timed infrastructure announcements with a splashy grand opening for the brand new span of the Mario Cuomo Bridge. Then came the "loud pop."

According to engineers, the concerning sound was first given off by the rickety remnants of the adjacent Tappan Zee on Friday evening, leading them to fear a "potentially dangerous situation" involving the former structure collapsing on the new crossing. By Saturday, Cuomo was left with no choice but to delay the opening of his father's bridge, over which he'd swaggeringly driven his favorite vintage car just one day earlier.

Cuomo's political opponents slammed the unsafe ribbon-cutting as "unconscionable, gross negligence," and some observers wondered whether he'd knowingly risked the safety of the public and his own mother for the sake of a politically expedient photo-op.

Somehow, this was not the worst thing to happen to the governor this weekend.

At the same time that Cuomo was sheepishly backpedaling on his signature infrastructure project, the New York State Democratic Committee, which the governor effectively controls, was stepping in its own self-made mess: Someone had signed off on a campaign flyer, sent to mailboxes across the city, attacking Cynthia Nixon for being "silent on the rise of anti-Semitism." 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. (In fact, she does not support BDS, and has hardly said a word about yeshivas throughout her whole campaign).

The mailers were swiftly and sternly rebuked by pretty much everyone—including politicians on both sides of the aisle, several rabbis, and the New York Times editorial board, which had offered a lukewarm endorsement of the governor only last week. When the committee's executive director, Geoff Berman, dutifully stepped in to take the heat for Cuomo, he hardly improved matters.

Though Berman has acknowledged that the mailer was "wrong and inappropriate," the state committee has thus far refused to answer repeated questions about how the deceitful ad got made, if anyone has been disciplined over the mistake, and whether it was targeted to certain demographics. Instead, Berman has vowed to work with the Nixon campaign to send out a separate mailer to the "same universe of people" that received the initial attack. (NY1 reports that universe is about 7,000 people).

But last minute snail mail won't repair the damage, according to Nixon, who's now demanding that the governor's camp robocall New Yorkers to disavow the flyer. During an appearance at Zabar's in the Upper West Side on Sunday, the candidate slammed the dog-whistle, adding that it "strains credulity" that Cuomo did not know about the decision.

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."

"It's the kind of thing you'd expect from Donald Trump," she added, cradling a cinnamon raisin bagel with lox.

During a press conference on Sunday—ostensibly about President Trump's tax plan, as it happens—Governor Cuomo flatly denied any responsibility for the screw-up. "I didn't know about the mailer, I heard about the mailer, I haven't seen the mailer," he told reporters.

Likewise for the threat posed by hosting a massive campaign event next to the still-crumbling Tappan Zee. "It's not our bridge," he said. "We are not responsible for it."

Anyway, Cuomo insisted, it was the contractor's decision when to open the bridge, and merely a "coincidence" that they'd deemed it ready just one week before the Democratic primary. Meanwhile, emails obtained by the Journal News suggest that Cuomo was directly involved in planning the opening of the first span of the bridge.

Nixon, in response, compared the governor's attempted dissociation from the scandals to his repeated buck-passing when it comes to the subway.

"He claims credit for something when he thinks it's an accomplishment and the minute that anything goes wrong, he says, 'Well you know we actually don't own that,'" she reportedly said, during a separate campaign stop in Tarrytown on Sunday. "This is such an old tired song from him."

Later in the evening, Terry Towle, the lead contractor for the Mario Cuomo Bridge, announced that the new span will open to traffic on Tuesday, though "there remains a possibility of the old bridge east span failing."

A new Siena Research Institute poll, which was conducted before the weekend, shows Cuomo leading Nixon by 63 percent to 22 percent among likely primary voters. The Democratic primary will take place on Thursday, September 13th.

Reporting by Jen Chung.

Subscribe to the Politics Brief newsletter for continued elections coverage

* indicates required