(CNN)Iowa Senate candidate Abby Finkenauer's name will appear on the state's June 7 Democratic primary ballot, the Iowa Supreme Court ruled on Friday, boosting the Democrat after a lower court had ruled she had not qualified for the primary.

       The court's decision makes Finkenauer the Democratic front-runner in the primary. The winner of that race will take on longtime Republican Sen. Chuck Grassley in November.

       Polk County District Judge Scott Beattie ruled earlier this week that Finkenauer's name "shall not be included on the primary ballot for the Democratic Primary for U.S. Senate" because of questions about signatures she received in two counties. The Finkenauer campaign appealed that ruling to the Supreme Court.

       "We reverse the judgment of the district court and direct that the petition be dismissed," the Supreme Court ruling read.

       The Iowa justices said the state's election laws -- including statutes focused on candidates qualifying for the ballot that were revised last year -- did not include missing dates among the reasons that signatures must be excluded.

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       "The date of signing might assist in verifying the petition if the signer was only an eligible elector for part of the time period during which the petition was being circulated, but it is hard to see why it would matter in any other context," the court said in its ruling.

       Six of the court's seven justices concurred with the ruling. The seventh agreed only with its result, and filed a separate concurrence.

       The court made the decision rapidly, with early voting just weeks away and clerks needing time to mail ballots to overseas voters.

       Finkenaur celebrated the decision on Friday.

       "The Iowa Supreme Court's unanimous decision today has affirmed that we are right on the law, and that we will be on the ballot for U.S. Senate," she said. "This is a moment for all advocates for democracy -- Democrats, Republicans, and Independents -- to celebrate the enduring strength of our democratic process and a reminder to never take it for granted."

       A pair of Republicans had challenged Finkenauer's candidacy, arguing that she had fallen short of the state's signature requirement -- 3,500 valid signatures, including at least 100 signatures from at least 19 counties -- because three signatures did not have dates.

       The Iowa Objection Panel, a three-member board that includes the Democratic state attorney general and auditor and the Republican secretary of state, voted 2-1 on party lines to keep Finkenauer on the ballot. But late Sunday night, Judge Scott Beattie, who was appointed by Republican Gov. Kim Reynolds, ruled that she had fallen short of the state's requirements and could not appear on the primary ballot.

       The Iowa Supreme Court heard oral arguments in the case Wednesday. Finkenauer's lawyer argued that state law did not require candidates to be removed from the ballot if dates accompanying signatures were missing.

       Finkenauer, a former congresswoman from Cedar Rapids, was among the first women elected to the US House from Iowa, winning election in 2018 along with Democrat Cindy Axne. She became the second-youngest woman elected to the House in history when she won at age 29. She lost reelection two years later to Republican Ashley Hinson.

       Finkenauer is the heavy favorite for the Democratic nomination in a primary that also includes retired Navy Adm. Mike Franken, who ran for the state's other US Senate seat in 2020, and Glenn Hurst, a Minden City Council member. But the primary winner would be a long shot against Grassley, who was first elected to the Senate in 1980. Iowa, once a presidential battleground, has shifted to the right in recent election cycles.