Philadelphia City Council passed the city’s historic and controversial tax on sweetened drinks in 2016 after intense debate and on a 13-4 vote.

But what will be the fate of the tax in 2020?

That may depend on the outcome of the May 21 primary election.

The tax, which funds pre-K, community schools, and the Rebuild program to improve parks, recreation centers, and libraries, is Mayor Jim Kenney’s signature achievement of his first term. As an incumbent, Kenney is favored to win the Democratic primary against his two challengers who oppose the tax: former City Controller Alan Butkovitz and State Sen. Anthony Hardy Williams.

The real battleground over the tax will likely be in Council, where candidates appear to have conflicted views on the 1.5-cent-per-ounce tax on soda and other sweetened beverages.

Of the 35 Democrats running for Council who responded to an Inquirer survey, 20 support the tax and 15 oppose it. All of the Republicans who responded to the survey oppose the tax.

» READ MORE: Where the Philadelphia City Council candidates stand on soda tax, other key issues

In interviews, however, candidates expressed more nuanced and conflicted views. Even the tax’s opponents voiced support for the initiatives it funds; some said they would simply like to see different revenue sources. And some who said they oppose the tax clarified that they would not vote to repeal it without a new funding plan in place.

“I think the actual question asked is a really hard one to answer,” said Erika Almirón, a Democratic candidate in the at-large race, who answered the Inquirer survey by saying she supports the tax.

Voters are also fairly split. An Inquirer poll — the first independent polling done about the tax — found 55 percent of registered voters would like to eliminate the levy. But asked whether pre-K should still be funded if the tax were eliminated, 62 percent of voters said a different kind of tax should be put in place.

Of the 865 voters surveyed, 62 percent said the tax was a failure or a complete failure, while 26 percent said it had been a success or complete success. Thirteen percent of voters said it was too soon to say.

Councilman Derek Green, who is running for reelection to an at-large seat and voted for the tax in 2016, said he still supports it. Green said that he has concerns about its impact but that it would be difficult to find another funding source for pre-K and other programs.

“People say, ‘We support the investment in pre-K, we support Rebuild,’ but where do you take the money from?” Green said. “It’s a little more convenient for those who are running for office [for the first time] to say what they would or would not do until they have a chance to vote.”

The tax’s supporters see it as a way to fund critically needed programs that improve the lives of the city’s children; some also see it as good public health policy to discourage the consumption of sugary beverages. Opponents, meanwhile, argue that its burden falls disproportionately on the low-income families the tax is designed to help, and that it has hurt businesses in the city.

The tax has remained controversial since it passed, with groups on both sides spending millions of dollars to fight for or against it. Other cities and states have had their own battles over similar taxes, and many politicians are closely watching Philadelphia.

The American Beverage Association is continuing to fight soda taxes in Philadelphia and across the country. The group spent more than $600,000 between April 2 and 18 on its Philadelphia campaign, according to its most recent campaign finance report, largely on television, radio, and online advertising.

“The Ax the Bev Tax coalition is spearheading a campaign to inform Philadelphians of the continuing damage that the tax is causing working families, small business and their employees, and that they have a chance to repeal the beverage tax now,” said Anna Adams-Sarthou, a spokesperson for beverage industry-funded group.

Harrison Morgan, a spokesperson for Kenney’s campaign, said the beverage industry “has shown they’ll stop at nothing to take away free pre-K from thousands of our children.” Morgan said Council candidates who oppose the tax should also explain why they would eliminate pre-K funding.

Current Council members have already taken action to evaluate and reconsider the tax. Legislation introduced last month that could phase out or eliminate the levy gained several cosponsors, and Council voted to study the tax.

» READ MORE: A timeline of Philadelphia’s soda tax

Sandra Dungee Glenn, a Democrat running for an at-large seat, said that “it’s definitely in the top five issues that come up” when she talks to voters.

“They definitely support pre-K and they don’t want to hurt pre-K,” she said. “They want to have another way to pay for it.”

Asa Khalif, a local activist running for a Democratic at-large seat, said he would like to consider ending the city’s 10-year tax abatement for new construction or rehabilitation projects and using it to replace the beverage tax revenue.

“The soda tax is not the way to do it,” he said, adding that the tax places the burden “on the backs of poor people and working people.”

Lauren Vidas, a candidate for the 2nd District, which includes Point Breeze and Graduate Hospital, responded to The Inquirer’s survey by saying she opposes the tax. But asked in person, Vidas offered a different answer: The tax is regressive, she said, but since it went into effect, she’d like to just make sure its revenue goes to the right programs. She is running against Councilman Kenyatta Johnson, who voted for the tax and indicated on the survey that he supports it.

“I don’t think it’s a great tax," Vidas said, "but I would not vote to repeal it.”

At-large candidate Eryn Santamoor supports the tax. But like most candidates interviewed, she offered a mixed response by saying she would like to broaden the funding streams for the beverage tax-funded programs to make sure they are sustainable. Santamoor also said she wished people would talk more about other issues.

“Can we talk about something else?” she asked. “There’s a lot of problems in this city we need to address."