Sykes, 38, defeated Republican Kevin Coughlin in a district centered on her native Akron, where she comes from a family steeped in state politics. Her father, Vern, is a sitting state senator and her mother, Barbara, is a former state lawmaker and statewide candidate.

"I want to congratulate Congresswoman Sykes on her re-election," Coughlin tweeted Wednesday morning. "While the result is not what we had hoped for, the values that drove this campaign -- safety, security, and affordability -- will still motivate us to create change."

Sykes still awaits a tie-breaking decision on whether an 11th hour challenge to her residency will proceed.

A political activist challenged her residency in the days before the election on grounds that her husband, Franklin County Commissioner Kevin Boyce, had listed Sykes as a member of his household in Columbus. Sykes called the allegation that she doesn't maintain residence in Akron "a deeply offensive lie."

The Summit County Board of Elections tied 2-2 along party lines on Oct. 24 on whether the challenge should be taken up. Board members had 14 days to deliver details of its disagreement to Republican Secretary of State Frank LaRose, who then, the law states, "shall summarily decide the question."

Kaptur, 78, had a slight lead over Ohio state Rep. Derek Merrin and declared victory based on leading the vote count in the wee hours of Wednesday, but The Associated Press has not called that race.

Kaptur entered the election cycle as among the most vulnerable congressional incumbents in the country. Her race for Ohio's 9th Congressional District attracted some $23 million in spending, as challenger Derek Merrin, a fourth-term state representative, won the backing of both House Speaker Mike Johnson and Donald Trump, the former and future president.

Her campaign cast her as overcoming "millions in outside spending from dark-money super PACs," and the Democratic Congressional Campaign Committee congratulated Kaptur as "a proven champion for the Midwest."

"As the longest serving woman in Congress, Marcy has never forgotten where she came from and never stopped fighting for Northwest Ohio," chair Suzan DelBene said in a statement. "She is a one-of-a-kind legislator, and leaders like her are few and far between. We are all better off with her in office."

The two parties spent more than $23 million in ads on the race between the March 19 primary and Tuesday, according to AdImpact, which tracks campaign spending. Democrats had a slight edge, spending more than $12 million to Republicans' $11 million. Merrin received more support from outside GOP groups than Kaptur, who spent about $3.7 million of her own campaign funds on the race after the primary.

A loss for Merrin would mark a rare failure of Trump's endorsement to lift a favored candidate to victory in the state, which he has won three times and stripped of its bellwether status. It worked to elect both U.S. Sen. JD Vance, now the vice president-elect, and Republican Senate candidate Bernie Moreno, who unseated incumbent Sen. Sherrod Brown on Tuesday.