A former Indiana school superintendent frantically overhauled a school grading system to ensure a Republican donor's charter school received an "A" grade.

Emails obtained by the Associated Press showed that former Indiana schools chief Tony Bennett, a Republican, insisted that a new school grading system must give the Christel House Academy charter school top marks.

The Indianapolis charter school was run by Christel DeHaan, who has given more than $2.8 million to Republicans since 1998, according to the Associated Press. Bennett had received $130,000 from DeHaan.

Bennett had promised to hold "failing" schools accountable by implementing the new statewide A-F school grading system. The new grading system had initially given Christel House a "C" grade, because of the school's poor test scores in algebra.

"This will be a HUGE problem for us," Bennett wrote in a Sept. 12, 2012 email.

At the urging of Bennett, the grading system was quickly altered so that Christel House ended up with an "A" grade.

Bennett told the Associated Press that he wasn't trying to tilt the system in favor of Christel House because of DeHaan's contributions. He said Christel House was a top-performing school and its "C" grade indicated the grading system was flawed.

Bennett is currently serving as Florida's education commissioner.

"You can judge Rick Scott by the kind of people he hires. Scott hand-picked Jennifer Carrol to be his running mate in 2010, but was forced to ask for her resignation after repeated scandals. Scott hired his long-time ally David Wilkins to run the Dept. of Children and Families, only to have him forced out by months of scandal and tragedy," Florida Democratic Party Chair Allison Tant said in a statement.

"And now we have found out that Education Commissioner Tony Bennett tried to bend the rules for an influential donor at his last job. If a teacher tried to fake a grade like that, she'd be fired. Floridians deserve answers. Is Bennett up to his usual tricks, doing favors for GOP donors? How can we trust Florida's school grades -- already the product of political manipulation -- with Tony Bennett in charge?"