U.S. Senate candidate Abby Finkenauer will appeal a judge’s ruling that says she cannot appear on Iowa’s June 7 Democratic primary ballot — a decision that has upended one of the state’s highest-profile political contests six weeks before early voting is set to begin.

The ruling late Sunday night, which reverses a state panel’s decision, is a major setback for Finkenauer, who is competing for the Democratic nomination to challenge Republican U.S. Sen. Chuck Grassley

Finkenauer, who has been widely considered the frontrunner in the Democratic primary, said Monday she would appeal the decision to the Iowa Supreme Court, casting it as “deeply partisan.”

“In a massive gift to Washington Republicans, this partisan decision overrules both the Republican secretary of state’s office and the bipartisan panel, ignores decades of precedent, interferes in the electoral process, and makes a mockery of our democracy,” Finkenauer said of the judge’s ruling.

The state’s seven-member supreme court has agreed to hear oral arguments in the case Wednesday and will likely issue a decision by the end of the week so election administrators can begin printing ballots to meet a federal deadline for overseas voters. 

Judge found signatures for Finkenauer were invalid

A pair of Republicans brought the challenge against Finkenauer, saying she failed to properly qualify for the ballot because she did not submit enough valid signatures on her nominating petitions.

More:Abby Finkenauer’s place on the Iowa primary ballot is being challenged. Here’s what to know.

A state panel last month found Finkenauer met the requirement, but Republicans argued the panel incorrectly allowed three signatures — one in Allamakee County and two in Cedar County — that did not include the date.

Polk County District Judge Scott Beattie said the panel’s interpretation of the law was incorrect and that the signatures should not be allowed to count.