The Sixers arena took center stage as City Council returned to session. A vote could come this fall.

One of the most powerful labor leaders in Philadelphia stood outside the City Council caucus room on Thursday, waiting to talk to lawmakers about a topic of mutual interest.

“A little thing called the arena,” said Ryan Boyer, chair of the Philadelphia Building and Construction Trades Council.

That little thing — the Sixers’ controversial plan to build a $1.55 billion basketball showplace in the heart of Center City — dominated the first day of City Council’s fall session, a preview of what is sure to be months of contention and drama.

Lawmakers were given the results of a new poll that shows voter opposition to the arena at 56%, demonstrators rallied against the project outside City Hall, and the Sixers warned that time was running out. New Jersey officials, meanwhile, are offering millions of dollars in tax benefits to try to lure the team to Camden.

Chinatown activists and their allies plan a big, noisy march through Center City on Saturday to oppose the arena, hoping to surpass even the size of a 2023 demonstration that closed streets and shut down traffic.

The Council session opened a little over a week after Mayor Cherelle L. Parker’s administration released four highly anticipated, city-sponsored studies on how an arena might impact economics, traffic, and community, particularly the Chinatown neighborhood that’s adjacent to the proposed site at 10th and Market Streets.

Many Council members had said they didn’t want to take a stance on the arena until the studies arrived. Still, no one was rushing to state their position Thursday.

Councilmember Mike Driscoll called the project “an exciting opportunity” but said he was still reading the hundreds of pages of information in the studies, and Councilmember Nina Ahmad said she was “still very agnostic,” with questions about the arena’s potential impact on tax revenue.

Councilmember Curtis Jones Jr., considered a Parker ally, said he needs “a lot more information” before deciding whether to support the development.

“I read the study, I read what the impacts are, but I have not seen what the solutions to those impacts are,” Jones said, citing potential burdens on transit, public safety, and Chinatown.

Majority Leader Katherine Gilmore Richardson said she needed more time to digest the studies, and Council President Kenyatta Johnson said the body was still conducting “due diligence.”

“We’ll work in partnership with the mayor, members of Council, in the event that a bill does come to the City Council to evaluate it,” Johnson said. “Until we get an actual bill as a body, we really can’t evaluate the details.”

Parker has not committed to backing the project, but her administration has been working with the Sixers to draft a package of arena-enabling legislation. If that’s presented to Council soon, Johnson said, it’s possible lawmakers could vote on the arena before the end of the year.

“We continue to have good, productive and thoughtful conversations with the city,” a Sixers spokesperson said Thursday, “and we hope to be able to come to an agreement that will allow the needed legislation to be introduced in Council in the coming weeks. … Time is running short for the 76ers to be able to construct a new arena in time for the 2031-32 season.”

More than 40 people rallied on the south side of City Hall on Thursday morning, voicing their opposition and calling on Council to reject the project.

Speakers said the arena would displace residents and businesses in Chinatown, provide few good jobs, and create choking game-day traffic that could block ambulances from reaching local hospitals. Thomas Jefferson University Hospital, a major city trauma center, is just south of the proposed arena site.

“I am urging City Council, please put health first,” said Rhicki Santos, a medical student.

Standing behind her, other students held signs that said, “Slower ambulances = more people die.” None would identify which schools they attend.

The Sixers say traffic can be managed, that surrounding parking lots are more than sufficient to handle arriving fans, and that their plan to build atop Jefferson Station will promote greater transit ridership.

The new city-sponsored analysis said the team’s goal of increasing transit use to 40% of fans, while another 40% travel by car, is attainable but not a foregone conclusion. Traffic would remain manageable if no more than 40% of event attendees drive, but even marginal increases in auto use beyond that threshold would result in gridlock at critical intersections, the study found.

Outside City Hall on Thursday, Brittany Alston of the Philly Black Worker Project, which seeks to educate people on the impacts of low-wage jobs and unemployment on Black communities, criticized politicians for aligning with the Sixers’ billionaire owners, saying the project “is not for or about working-class Black folks.”

Several times during the rally, speakers put the question to Parker and City Council: Who do you work for?

“This is about more than saving Chinatown, it’s about preserving the soul of our city,” said the Rev. Robin Hynicka, lead pastor of Arch Street United Methodist Church. “I ask the mayor, Mayor Parker, and City Council, particularly Councilman [Mark] Squilla, who will you listen to? The people who vote, or the people who pay to get your attention?”

Squilla is a key player, his 1st District containing both the arena site and Chinatown, and Philadelphia’s tradition of councilmanic prerogative granting him enormous sway.

The arena would claim the western third of the Fashion District mall, covering the area from 10th to 11th and Market to Filbert Streets and bringing, the team says, new economic vitality to struggling Market Street East. The Sixers promise the arena will be built with private money, without city tax dollars, although they’re open to state and federal funding.

The team’s Wells Fargo Center landlord, Comcast Spectacor, has been working to get the Sixers to stay at the South Philadelphia sports complex — including proposing an alternate vision for the Fashion District, as a biomedical Innovation Hub. The Wall Street Journal recently reported, however, that while biotech and pharmaceutical buildings were a hot investment at the start of the pandemic, the glut of life-sciences properties has become so severe that developers are considering marketing the space for offices.

Council members were given the results of a new citywide poll that found 56% of Philadelphia voters oppose a downtown Sixers’ arena. Only 18% support it.

The poll was commissioned by the Save Chinatown Coalition, one of the groups fighting to stop the project, and conducted by Cornell Belcher of brilliant corners Research & Strategies in Washington, D.C. The firm previously did campaign polling for now-Mayor Parker, for the presidential campaigns of Barack Obama, and for the Democratic National Committee.

Those opposed to the arena cited two top reasons: a belief that the project would increase downtown traffic and that it would hurt Chinatown.

“I seldom see such strong intensity in opposition to an arena,” Belcher said at a news-media briefing on Wednesday.

The poll was based on 704 registered voters who were contacted by phone by professional interviewers from Aug. 22 to Aug. 25. The overall margin of error was 3.7%.

Fully 80% of respondents were concerned that event-day traffic would impede access to the emergency room at Thomas Jefferson University Hospital, south of the proposed site.

Voters identified issues including drug use, education, housing, and homelessness as top priorities for the attention of the mayor and Council. Only 12% said building a new arena was a priority.

“The more voters hear about the proposal, the more they dislike it,” said Mohan Seshadri, executive director of the Asian Pacific Islander Political Alliance, a member of the Save Chinatown Coalition.

The personal lobbying of Boyer, the labor leader, underscored how the arena is likely to dominate City Hall in coming months, his presence reinforcing what Council members already know: The more than 30 unions in the labor council want the years of work that an arena would promise.

What, he was asked, is the trades’ position on the issue?

“Construction jobs,” Boyer answered.