SACRAMENTO (CBS SF/AP) — County officials from across California are weighing in when they will be ready to hold the recall election of Gov. Gavin Newsom.

They say they can’t do it until at the earliest mid-September.

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“The California Association of Clerks and Election Officials (CACEO) members are committed to running an efficient, accurate, cost-effective, and transparent election,” the group wrote in a Monday letter to Lt. Gov. Eleni Kounalakis. “We urge the Lieutenant Governor’s office (to) take our concerns seriously, which will allow us to conduct a successful election process. We owe this to our voters.”

The election date remains uncertain. While the state has signaled the recall has qualified for the ballot, several convoluted steps remain before it is certified to go to voters. Among them: formally estimating the cost of the election.

Democrats who control the Legislature already voted to give counties $215 million and are trying to change the recall law to speed up the process, potentially allowing the recall to be scheduled by late summer. Meanwhile, the county clerks are warning against moving too fast.

Many California counties mailed everyone a ballot before the pandemic, but for the 2020 election the state required all counties to do so because of coronavirus concerns. Lawmakers extended that rule for 2021 elections, meaning more paper costs for local officials.

Printers that supply the majority of the state’s counties with ballots told local officials they can’t provide materials to hold an election any earlier than Sept. 14. Because the contest hasn’t been certified, officials still don’t know how many candidates will run and how much paper they’ll need. In the 2003 governor’s recall, more than 100 people sought the office.

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The clerks also noted some counties need to recruit poll workers in up to 14 different languages, with a training process than can take two to four months. That process is even harder in the summer, they said. Their letter lists a host of other potential logistical problems, including the trouble of renting vehicles to help transport ballots and set up vote centers during the summer travel season.

The recall will be California’s only statewide election this year, coming about a year before Newsom’s regularly scheduled 2022 reelection.

Republicans already running against him include former San Diego Mayor Kevin Faulconer, businessman John Cox, reality TV star Caitlyn Jenner and former congressman Doug Ose.

On Tuesday, Secretary of State Shirley Weber announced all candidates running in the recall must release their five most recent years of tax returns. The Democratically-controlled Legislature passed a law requiring candidates for governor to release their returns in 2019. But the law applies to candidates running in a primary and is silent on a recall, and someone may challenge Weber’s interpretation.

Ose and a spokesman for Faulconer said they would release their returns. Anthony Ramirez, a spokesman for John Cox, said Cox would be on the ballot but did not directly answer whether he would release his returns. A spokesman for Jenner said “the campaign will meet all requirements of the recall election.”

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Newsom released his 2019 tax returns in May. He requested an extension on his 2020 returns and has not yet filed them.