CHICAGO — A $260,000 donation to Illinois Comptroller Leslie Munger’s campaign has lifted the caps on political contributions and guarantees a big-money race between the Republican incumbent and Democratic challenger Susana Mendoza.

The loan is from Munger’s husband, attorney John Munger, according to an Illinois State Board of Elections filing late last week. State campaign finance law limits donations, but it also says if a candidate or family member contributes more than $250,000 to his or her own race, the limits come off for all candidates.

The move comes as millions of dollars are being funneled into Illinois legislative races and Republicans are outspending Democrats for the first time in recent history. Backed by a wealthy governor Republicans are attempting to break Democratic supermajorities in the House and Senate.

Gov. Bruce Rauner appointed Munger last year following the death of Judy Baar Topinka. The winner of the November contest, which includes Libertarian and Green party candidates, will finish the remainder of the four-year term.

With no caps, both Republicans and Democrats are sure to pour resources into the race. The role of the comptroller, who writes the state’s checks, has taken on more prominence during the state’s budget stalemate because the office gets to prioritize who gets paid and who has to wait.

Munger and Mendoza have tried to cast their opponents as extensions of Rauner and House Speaker Michael Madigan, who serves as the Democratic party chair and controls campaign funds.

Munger campaign spokesman Phillip Rodriguez accused Mendoza, Chicago’s city clerk who was a former state legislator, of aligning her legislative votes with Madigan.

“With this contribution, Comptroller Munger is balancing the playing field and demonstrating her complete commitment to standing up for Illinois taxpayers,” Rodriguez said in a statement.

But Mendoza’s campaign manager Lauren Peters said the move means Munger can take “unlimited money” from Rauner and “continue to be a wholly-owned subsidiary of the governor.”

“Even by Illinois standards, this is beyond the pale,” she said in a statement.

State campaign finance law says individuals can give $5,300 and political action committees can donate $52,600. The changes in campaign finance law came after now-imprisoned former Gov. Rod Blagojevich was accused of trying to sell President Barack Obama’s vacant Illinois Senate seat.

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