City Councilman James Kenney said Thursday that he would decide "in the next week or so" whether to enter the Democratic primary race for mayor.

Kenney, who has vacillated for months on the question, appears more likely now to enter the field. And he may have strong support from a coalition of labor unions.

"It feels more real," Kenney said.

Three recent events have influenced Kenney's thinking:

City Council President Darrell L. Clarke, first choice for mayor among some union leaders, last week said he would instead seek a fifth term on Council.

City Controller Alan Butkovitz, who dropped plans for a mayoral bid in November because he was uncertain what Clarke would do, has not reversed course.

Former City Solicitor Ken Trujillo dropped out of the mayor's race Wednesday.

Kenney said he plans to meet with Trujillo's campaign staff to discuss his plans. "I'm going to talk to the folks involved to see what they have to say and what they think," Kenney said.

Some of those staffers worked last year on the successful bid by now-U.S. Rep. Brendan Boyle, a Democrat who had significant support from the city's building trades unions when he won a district that straddles Philadelphia and Montgomery County.

John "Johnny Doc" Dougherty, leader of Local 98 of the International Brotherhood of Electrical Workers, hosted at his union's headquarters a monthly meeting of labor leaders Wednesday. Dougherty on Thursday called Kenney a "dark horse" candidate who could win the race, similar to Mayor Nutter's move in 2007 from a Council seat to the mayor's office.

Dougherty said labor leaders representing police, firefighters, blue-collar workers, hospital workers, and construction workers are so far unimpressed with the Democratic field, which now includes three declared candidates - former District Attorney Lynne M. Abraham, former Common Pleas Court Judge Nelson A. Diaz, and State Sen. Anthony H. Williams.

"There's no urgency to be for anyone else," Dougherty said. "Everyone is just not enthused by what's going on right now."

One of those labor leaders, Henry Nicholas, said he pushed for Kenney during Wednesday's meeting.

"He has the best voting record on workers' issues in City Council," said Nicholas, president of the National Union of Hospital and Health Care Employees. "I'm hopeful that within the next two weeks he will emerge as a unified labor candidate."

That could mean significant resources spent on Kenney's behalf.

Dougherty said the labor coalition that met Wednesday, known as Workers Stand for America, may file to make "independent expenditures" in the mayor's race.

"IE groups," as they have come to be called, can spend unlimited amounts of money to influence an election as long as they don't coordinate the effort with a candidate.

The city's campaign-finance law limits political contributions to $2,900 for individuals and $11,500 for political committees.

The building trades unions last year formed an independent expenditure group to support Boyle's bid for Congress.

That group, dubbed Building a Better Pennsylvania, spent $354,032 on TV ads supporting Boyle and criticizing his opponents in the two weeks leading up to the primary election. Much of the group's funding came from Dougherty's union.

Kenney has already taken on one of his potential foes in the Democratic primary. He asked the city Board of Ethics for an opinion last week on whether former Nutter aide Doug Oliver could keep working for the Philadelphia Gas Works while gearing up to run for mayor.

Kenney said he was concerned that Oliver was receiving valuable "face time" via a PGW television commercial that could benefit his campaign. Oliver, who plans to formally announce his campaign Feb. 7, resigned from the publicly owned utility last week.

Kenney, 56, has taken several high-profile positions during his sixth term on Council.

He took on the president of Chick-fil-A in 2012 for opposing same-sex marriage. He pushed through a bill to decriminalize penalties for small-amount marijuana possession, and feuded with Nutter over it until they came to a compromise in October. And he pushed in September to expand the city's hate-crimes legislation after a Center City attack on a gay couple.

Dougherty said the union coalition is ready to write checks, collect signatures for nomination petitions, and anything else a mayoral candidate needs.

"We have the footprint for a working-families campaign," Dougherty said. "We just don't have the candidate yet."