An election watchdog group has filed a complaint against an independent political committee that is supporting a union-backed slate of Douglas County school board candidates.

Campaign Integrity Watchdog filed the complaint against Douglas Schools for Douglas Kids with the Secretary of State earlier this week. The complaint alleges that the political committee, which can spend an unlimited amount of money to advocate for candidates, failed to file timely and accurate campaign finance reports.

The complaint stems from confusion over contributions from the American Federation of Teachers, the nation’s second largest teachers union, to the political committee.

A report filed by the committee shows one contribution from the union. However, other records filed by the union make it appear like there were two contributions — both $300,000 — from the union to the same committee. One donation is from “American Federation of Teachers” the second donation is from “American Federation of Teachers Solidarity.”

The union, responding to questions from Chalkbeat, said the double reporting was a clerical error made in an attempt to amend its original report and that it only made one $300,000 donation to the committee.

“It’s possible they screwed up the reporting,” said Matt Arnold, director of Campaign Integrity Watchdog, which has lodged complaints against both Republicans and Democrats in partisan races (school board elections are nonpartisan). But, he said, “voters deserve to have information about who is trying to buy and sell their votes.”

The union said it is trying to clear up the error with the state.

The race for control of the Douglas County school board is one of the most heated contests in Colorado this fall. At stake is the district’s private school voucher program, which has been tied up in the court system since 2011.

Right now, the board is split 4-3 in favor of keeping the voucher fight going. Four seats are in play this election, so that direction of the board is at stake.

The union-backed candidates are running as the “CommUnity Matters” slate and hope to end the district’s defense of the voucher program. Their opponents, the “Elevate Douglas County” slate, are seeking to keep the legal fight alive.

The high-profile nature of the race has drawn national attention and dollars. And that’s becoming a recurring theme in Colorado school board elections. More than $1.5 million from outside groups already has flowed into the races along the Front Range.

“What’s really striking is how much money has been pouring in these school boards races in Colorado,” Arnold said.