Nine of the council's 13 members co-introduced the bill, which is also supported by D.C. Attorney General Karl A. Racine and a coalition of advocates who say it would increase the power of small donors and open the field to candidates not backed by big campaign contributors.
Bowser, whose critics say she is too closely linked with developers and other corporate donors, thinks taxpayer dollars should go toward the "many pressing needs" of residents instead of a public finance program, Bowser spokeswoman LaToya Foster said. Bowser's position was first reported by WAMU-FM (88.5).
"It is not prudent to divert tax dollars from hiring more police, investing in housing or fixing our roads to paying for candidate robo-calls, pole signs or donor receptions," Foster told The Washington Post.
The public finance program, if passed by the council, would not be in place until 2020. It would cost taxpayers about $5 million per year — a tiny fraction of the city's $13.8 billion budget.
D.C. Council Member David Grosso (I-At-Large), who authored the bill, said if Bowser does not support the program, it could "leave a bad taste in the mouths of voters and advocates" as she campaigns for reelection this year.
If Bowser does not choose to fund the bill in her budget, the council can allocate money for the program, he said.
"But there is still time for her to come around," said Grosso, who added that Bowser has made efforts to end the perception of a pay-to-play culture that has long plagued the Wilson Building.
But a Washington Post poll this summer showed District residents rate Bowser negatively on her efforts to curb the influence of wealthy political donors by a margin of 48 percent to 31 percent.
In June, Bowser's campaign committee was ordered to pay $13,000 in fines for taking campaign donations in excess of legal limits, including thousands of dollars in illegal contributions from developers and contractors during her run for office in 2014. She has raised more than $1.4 million since she announced her reelection bid in late September.
Craig Holman, a government affairs lobbyist at the nonprofit group Public Citizen, said Bowser's position on the public finance program "is going to backfire on her."
"She has now staked out very unpopular territory," said Holman, who added that he thought Bowser might "at least remain neutral" because Racine and council member Vincent C. Gray (D-Ward 7), who were considered possible challengers to her reelection, support reforms.
But because Gray has not announced whether he will challenge Bowser, and Racine has said he will seek reelection as attorney general, Bowser "may feel comfortable enough in this race that she is expressing what she really feels," said Holman, who helped draft a campaign-finance reform bill for Gray when he was mayor.
Both Racine and Gray have introduced bills to ban political contributions from donors seeking contracts with the city.
Those efforts are largely seen as a response to a PAC set up by Bowser associates after her 2014 mayoral victory that sought contributions of $10,000 or more from individuals and companies, including some seeking contracts with the city. Bowser's supporters closed the PAC under pressure, after developers and executives who had made donations accompanied the mayor on a trip to China.
Racine said his office and the majority of council members have been "clear and consistent" in supporting laws that "seek to eliminate or reduce the perception of pay-to-play politics in the District of Columbia."
"It is clear that voters are sick and tired of having to be concerned about instances where contractors win contracts and happen to be extremely large donors," Racine said.