Ben Kallos Skewers Micah Kellner in Anonymous Mailer

The anti-Kellner mailer from the Kallos camp.

The anti-Kellner mailer from the Kallos camp.

Assemblyman Micah Kellner’s leading rival doesn’t want the Upper East Side to forget about his summer scandal as the two candidates battle for an open City Council seat.

In a new, biting campaign mailer, rival Ben Kallos blasts Mr. Kellner for admitting to sending inappropriate communications to a female staffer and allegations of even more misconduct. “Those around Kellner tried to bury the charges, keeping them secret for years as the harassment continued–a massive Albany cover-up over which one Assembly lawyer has already been forced to resign,” the mailer rages.

But in a move that raised some eyebrows in the district, the ad does not disclose that it came from Mr. Kallos, who has been explicitly branding himself as one of the most good government-touting, pro-transparency candidates anywhere in the five boroughs.

The Kallos campaign acknowledged to Politicker that the mailing had come from them and trumpeted it as a public service of sorts–despite the fact that it lists no information about who funded the effort.

“We own it completely and think it’s crucial that voters know the facts,” a Kallos spokeswoman said.

The other side of the mailer.

The other side of the mailer.

Mr. Kellner, however, called the mailer, including other ones sent out by the Kallos campaign, “desperate, inaccurate and anonymous.”

“Unfortunately, my opponent Ben Kallos has resorted to desperate, inaccurate and anonymous attacks,” Mr. Kellner told Politicker in response. “I don’t believe in the politics of personal destruction. I believe public service is about making a real difference for New Yorkers. That is why I am running for City Council.”

David Nir, political director for the online progressive community Daily Kos, who originally forwarded the negative mailer to Politicker last week, said he had flipped his vote to Mr. Kallos after the Kellner scandal, but now could support neither.

“Kellner deserves to be criticized, but not anonymously,” said Mr. Nir. “Now I think I won’t vote for either candidate.”

Colin Campbell contributed reporting.

Ben Kallos Skewers Micah Kellner in Anonymous Mailer