PHOENIX — Renewable energy advocates in Arizona won ground in an election over the future of Salt River Project, Arizona’s largest public power utility, as voters weighed electricity costs and the growing footprint of data centers. The election, which wrapped up Tuesday, ended with a clean-energy slate gaining two seats on the utility’s 14-member board, giving it an 8-to-6 majority in votes that come before the board. But the results also preserved the agenda-setting power of incumbents backed by construction firms and data center developers, who retained the presidency and vice presidency.

The board race played out as demand for electricity rose in Phoenix-area data center corridors, and as the utility faced pressure to add capacity while cutting reliance on fossil fuels such as coal and natural gas that emit planet-warming greenhouse gases, the reporting said. The election drew more attention than past utility board contests, in part because household electricity prices have climbed and national politics became more closely tied to local races, the reporting said.

Randy Miller, a renewable energy advocate who won a seat on the board, said the slate was disappointed it did not win the president and vice president roles but that the new majority would require negotiations. “We’re a little disappointed by not winning president and vice president, but now we have a majority, so we’re going to have to do a little negotiating,” Miller said. Under SRP’s governance structure described in the reporting, the incumbents’ control of president and vice president keeps the slate from setting which votes reach the full board first.

The rival slates now face choices that go beyond board control, including whether SRP should increase rates and how it should power growing data center demand. The reporting said the clean-energy slate argued the majority’s approach was too eager to hook up to natural gas, raise rates and embrace data-center growth, while members of that slate have previously voted against major natural gas projects by SRP and against a rate increase last year.

In the campaign, national political attention also landed on SRP’s board race, with Turning Point Action attacking the renewable energy advocates as “radical environmentalists.” The reporting said the group is better known for mobilizing young conservatives behind President Donald Trump, and that it was brought into the debate as the election stirred voters.

Incumbent backers warning in the reporting about the consequences of moving away from natural gas pointed to a risk of tight energy supplies and blackouts, particularly if SRP reduces reliance on gas-fueled power plants. The clean-energy team, meanwhile, sought greater emphasis on renewable energy technologies as SRP plans for the longer-term buildout needed to double its power capacity within a decade, the reporting said.