While the election for City Council speaker is still months away, last week’s primary results are now shaping the dynamics of the race for the council’s top job, being vacated by term-limited Christine Quinn.

Of the council’s 51 members, 21 will not be returning next year, either because of term limits or lost elections.

At the first post-election meeting of a half-full City Council on Thursday, council members were mum about their preferences for new leadership. But those aligned with the left-leaning Progressive Caucus Alliance acknowledged that their ranks were likely to grow – and that this could carry new influence.

City Council Progressive Caucus co-founded Melissa Mark-Viverito has made known her intentions to vie for the City Council speaker’s post. Photo: City Year/Flickr

Caucus founding member Jumaane Williams did not respond directly to whether the coalition would seek to vote as a bloc for the speaker, speaking instead of a body “formed to have some strength when saying something.”

“We’re going to try to make sure that voice is heard on all issues,” he said.

The caucus, launched 2010 by Councilmembers Melissa Mark-Viverito and Brad Lander, has grown to 11 members, 10 of whom are assured of reelection. (Councilmember Letitia James is running for public advocate.) It could now expand its ranks to as many as 18 after the group’s endorsement of a handful of Democratic candidates who are either running unopposed in November or who will vie with a Republican candidate but are expected to win.

Ben Kallos and Mark Levine, both of Manhattan, as well as Ritchie Torres of the Bronx have all committed to join the caucus if elected. Daneek Miller of Queens, too, said he would join the caucus when he was asked in a number of endorsement interviews with labor and other groups, spokesperson Corey Bearak said.

Another two, Antonio Reynoso and Carlos Menchaca, were backed either by the caucus or a caucus member, but it is not clear whether they will formally commit. And caucus-endorsed candidate Costa Constantinides, who must still win his general election, has also been tight-lipped about what he will do next. Finally, paper ballots are still being counted in the Brooklyn race, too close to call, where Progressive Caucus–endorsed candidate Kirsten John Foy is running.

In all, the caucus stands to gain as few a four and as many as eight new members in the new City Council, if candidates endorsed cement their relationship with it.

While that falls short of the 26 votes needed to secure a majority in the council, it may be big enough to have an influence on the selection of speaker, which historically has been controlled by the Democratic Party machinery in the boroughs.

The caucus will be “a powerful bloc when the Council votes in January on their new speaker,” suggests Evan Thies, a political consultant who is not working with the Progressive Caucus candidates.

The caucus’ political clout “shifts the dynamic” of the speaker’s election, Thies said, by offering an alternative to the voting cues democratic county leaders in Queens, Brooklyn and the Bronx have traditionally given council members.

“Whereas traditionally the speakership was always decided by at least two, usually three of the county leaders, what you have now eight years after the last speaker’s election is a city with an emerging independent streak of politicians,” Thies said.

The position of speaker is a coveted one, transforming the victorious councilmember into a power broker who exercises broad control over which bills are brought to a vote, appoints committee members and apportions how much members can spend.

Caucus co-chair Melissa Mark-Viverito, a councilmember whose district is split between Manhattan and the Bronx, is one of three candidates who have openly announced their interest in becoming speaker. The other two are councilmembers Inez Dickens and James Vacca. Councilmembers Mark Weprin, Dan Garodnick and Annabel Palma have been rumored to be interested in the job.

Non-affiliated councilmember Rosie Mendez of the Lower East Side played down the prospect of a unified front. “Quite frankly, the caucus has never voted as a collective before,” Mendez said.

Parkside Group political consultant Jake Dilemani suggested that certain candidates who have spoken about joining the Caucus “may not necessarily vote the caucus’ way for speaker.”

Noted Dilemani, “Some of these candidates have close relationships with other political elements.”

Council members expect Democratic nominee Bill de Blasio to weigh in on the speaker’s contest in the Democratic-majority council should he be elected mayor.

“You might have seen some differences for a speaker choice depending on who was the Democratic nominee,” said Councilmember Mendez.

On Thursday, seven members and Democratic primary winners affiliated with the Progressive Caucus or backed by it during their election endorsed de Blasio at an event touted as a “rally for progressive change” in Brooklyn.

But the Parkside Group’s Dilemani said that a liberal mayor, or one perceived as such, would potentially push for a moderate speaker in order to protect himself from attacks, from either the left or the right.

Should de Blasio become mayor, the caucus stands to gain from the jockeying that typically takes place in choosing the speaker, says Kenneth Sherrill, political science professor emeritus at Hunter College.

“If de Blasio wants to install his own person as speaker, which wouldn’t surprise me, then it might be that the Progressive Caucus would be a key ally of his as he bargains with the county organizations to obtain the votes that he needs,” Sherrill said.

“I think that what this means is that they will get some key committee chairs.”

GOP councilmembers are another wild card.

Queens Republican Councilmember Eric Ulrich said he hoped the group would vote as a bloc for the next speaker.

Who that vote will go to remains undecided, he said, but the Progressive Caucus’ Mark-Viverito was the current Republican councilmembers’ “least favorite.”

Update: Democratic nominee in Queens Costa Constantinides “is planning to join the City Progressive Caucus if elected,” his communications director Shachar Sharon confirmed in an email. Constantinides will face Republican candidate Daniel Peterson in the November general election.