Boston’s City Council Wednesday approved Mayor Michelle Wu’s proposal to spend $8 million in federal pandemic relief funds on expanding fare-free bus service in the city for the next two years.

The pilot program, once formalized with the MBTA, will bring Boston from one free bus to three. Wu’s administration says that the trio will form a focused web within the city center where residents are underserved by rail service. The new pilot is also intended to ease financial burdens for riders along the three routes, 28, 29 and 23, which serve riders who travel to and from Dorchester, Mattapan and Roxbury.

The approval came via a 12-1 vote, with Dorchester City Councilor Frank Baker as the lone “no.”

The expanded pilot program gives the new Wu administration one of its early victories, bringing Boston a small step closer to her vision of free public transit.

Wu, who faced vigorous criticism for the idea on the campaign trail earlier this year, said in a social media statement she looks forward to working with the MBTA to launching the program.

Boston's current free bus pilot, Route 28, was scheduled to conclude at the end of the year after being launched and extended once by former acting Mayor Kim Janey.

The 28 bus carried about 12,500 riders daily prior to the pandemic, more than two-thirds of whom were classified as low-income, according to the MBTA's most recent, system-wide survey.

That single pilot was estimated to cost $500,000, a figure that Wu described as an "overpayment" at one point while campaigning.

The $8 million, Wu administration officials have said, factors in ridership estimates along the 28, 29 and 23 routes based on pre-pandemic ridership, which the MBTA has struggled to recover since COVID-19 began ravaging the economy. The figure also factors in costs for marketing and pilot evaluation.

The new pilot will also solidify Boston among a handful of governments nationwide turning to free bus service programs as a means of spurring pandemic recovery and reducing traffic and carbon footprints. Kansas City, Mo., and Olympia, Wash., have both implemented free bus rides. More locally, the Worcester Regional Transit Authority and the city of Lawrence have begun offering some form of fare-free bus service.

In Colorado, Gov. Jared Polis has asked lawmakers for $28 million to fund free bus and train rides across the state on bad pollution days.

Massachusetts Gov. Charlie Baker, who revealed he is declining to seek a third term Wednesday, has indicated he would be open to the idea if Boston found a way to fund it.

Wu, who has not endorsed any candidate in the gubernatorial race, said Wednesday she looks forward to working with the Baker administration on transit issues for his remaining time in office. She added that candidates' positions on fare-free transit would factor into her evaluations of those running for governor of Massachusetts.

Wednesday's council vote came as Janey returned to preside over the council proceedings as president. Even though she served as acting mayor for several months, she technically still retained the title.

Erin Murphy, who won one of the council's four At-Large seats this year, was also sworn in to an early start on the council Wednesday, filling the gap left when Wu ascended to the mayor's seat.

Murphy was previously scheduled to be sworn in along with the rest of the crop of new councilors in January, but several councilors had ethical concerns about another person, Boston Cannabis Commissioner Alejandra St. Guillen, serving in Wu's stead for the remaining three meetings. St. Guillen was initially slated to take Wu’s slot based on her fifth-place finish in the 2019 At-Large council elections, where Murphy placed sixth.

On Wednesday, Murphy voted and debated along with the other councilors on the free bus pilot expansion proposal.