State schools Superintendent Joy Hofmeister was charged Thursday with campaign fundraising violations and conspiracy.

The Tulsa Republican is accused of illegally colluding with a dark money group to win election in 2014. Prosecutors allege she used the group, Oklahomans for Public School Excellence, to secretly accept illegal excessive donations and illegal corporate donations.

She has denied wrongdoing.

She faces two felony counts involving donations to the dark money group and two felony counts of conspiracy.

Charged with her in the conspiracy counts are Fount Holland, her chief campaign consultant, and Stephanie Milligan, the dark money group's political consultant.

Milligan is currently involved in Donald Trump's presidential campaign.

Also charged in the conspiracy counts are two former leaders of state education organizations -- Lela Odom, who in 2014 was the executive director of the Oklahoma Education Association and Steven Crawford, who was the executive director of the Cooperative Council for Oklahoma School Administration. Prosecutors allege they helped create and fund the dark money group.

Oklahoma County District Attorney David Prater filed the charge Thursday after a two-year investigation that involved multiple interviews and the review of thousands of emails and text messages.

The evidence found to be significant in the case is described in a 28-page affidavit. Hofmeister was interviewed for the investigation in June and stated then she had no specific knowledge of the dark money group other that that there would be one, according to the affidavit.

Providing the primary funding to the dark money group was the Oklahoma Education Association and the Cooperative Council of Oklahoma School Administration. They donated a total of $300,000 to the group, using $100,000 they accepted from an insurance company, American Fidelity, according to the affidavit.

The insurance company is not accused of wrongdoing.

One email revealed Hofmeister wrote in 2013 that "this independent campaign" -- using money from the OEA and CCOSA -- "would do ... negative ads and allow me to take the high road with my own campaign."

"The conspirators used these funds to finance a negative campaign ad focused on Hofmeister's opponent, Janet Barresi," the district attorney's chief investigator wrote in the court affidavit. "Such expenditures are required to be made independently and without coordination with a candidate ... to avoid becoming illegal corporate and/or excessive contributions to the candidate."

Prosecutors allege there is evidence of illegal coordination involving an ad the dark money group ran attacking Barresi, then the incumbent schools superintendent.

That ad depicts an apple rotting on a desk in a school classroom as the narrator makes statements critical of Barresi. The statements also appear in chalk on a blackboard. The last statement is: "Janet Barresi, a BAD APPLE when it comes to education."

The ad's creator, Bob Kish, told investigators Holland steered him to the dark money group, according to the court affidavit.

Prosecutors say they have evidence the Hofmeister campaign shared polling data with the dark money group. Prosecutors allege this allowed the group to target specific cities to run the ad.

Investigators reported Hofmeister and others referred to Oklahomans for Public School Excellence as the Independent Expenditure or IE. Investigators reported finding Hofmeister in one email wrote of a wind turbine lobbyist's interest in donating to "my IE."

"The subject matter and content of emails indicate Hofmeister had knowledge of events that should have been unknown if the IE was truly independent," the district attorney's chief investigator wrote.

Considered a key prosecution witness in the case is Ryan Owens, the current executive director of CCOSA. Prosecutors allege he was the registered agent for the dark money group at the same time he acted as an adviser and speechwriter for Hofmeister's campaign.

He told investigators he removed himself as the registered agent after getting a frantic call that Hofmeister's consultant, Holland, was upset, according to the court affidavit. Owens wrote in an email, "Joy and crew are freaking out!"

During an interview with investigators, Owens advised that Holland "pressured him monthly for details about what the IE was doing," according to the court affidavit.

"He wanted to know how much money the IE had, when the IE was going to run an ad and who was producing the ad," according to the court affidavit. "Owens admitted that he shared this information with Holland. ... Owens advised investigators that, after being pressured by Holland and Hofmeister, he shared with them that OPSE had $300,000."

In text messages in June 2014, Hofmeister wrote of her worry a "dark money" negative ad could backfire, handling Barresi "a golden opportunity," according to the court affidavit. She also wrote, "Obviously, we can't do anything about the IE." She adds to that sentence a "smiley face emoticon," according to the affidavit.

Owens told investigators he felt Hofmeister was asking him in those text messages to have Milligan stop the ad, according to the court affidavit. "Owens felt he was being asked to do something that was clearly illegal."