D.C. Council member David P. Grosso (I-At Large) ((Courtesy of David P. Grosso))

D.C. Council members are known to say nasty things about one another, even in public or with TV cameras rolling. But at election time there’s long been a red line: Incumbents stick together. Or, if they have nothing nice to say, they say nothing at all.

That is, until this week.

Council member David Grosso (I-At Large) sent the Wilson Building atwitter on Tuesday with news he’d recorded a robocall on behalf of Brianne Nadeau, a challenger to longtime Ward 1 council member Jim Graham (D) in his reelection bid.

Graham is seeking a fifth term on the council against a field a competitors, including Nadeau and Bryan Weaver. The challengers have sought in part to make the election a referendum on Graham’s ethics record, including his role four years ago in intervening in a city lottery contract.

When the council reprimanded Graham for that action last year, Grosso said he would not support Graham if he sought reelection.

In three robocalls, which were first reported by Washington City Paper, Grosso does not mention the ethical flap involving Graham, but he says Nadeau will bring “positive change” to the council.

“Support Brianne Nadeau, my choice for the Ward 1 D.C. Council seat,” Grosso concluded each call. “Brianne is the positive change we need and will bring new energy to the D.C. Council.”

Graham downplayed the significance of Grosso’s endorsement on Tuesday. “Having a non-Democrat comment on a Democratic primary won’t mean much,” he said. “My opponent is grasping for straws – and she got one.”

Grosso acknowledged in an interview that he was breaking with tradition among council members.

“I think it’s probably fairly unusual,” he said. “But if my colleagues don’t know by now, I don’t often dance to the same drumbeat.” He encouraged other council members to follow suit and “stand up and endorse when it’s necessary to get involved in campaigns.”

Grosso also said that his support for Nadeau is “not so much against someone as it is for her. And in the long run, it’s about looking for a new direction on the council, something I’ve stood for on the council and long before.”

Nadeau said she was honored by Grosso’s support, especially since the council member, who serves on two committees with Graham, will continue to have to work with him side-by-side.

“I am flattered to have the support of an incumbent council member – especially one who espouses the same values we bring to the race,” Nadeau said, adding that she welcomed the campaign help from an independent.

“He’s council member for the entire District,” Nadeau said. “Those of us who are looking for progressive change on the council have looked to him, regardless of his party.”

In 2012, Grosso won the support of at least 5,000 Democrats in Ward 1.