Voter participation rates approached presidential year levels in some states, including Wisconsin, Minnesota, Montana, Oregon and Colorado, where more than 60 percent of eligible voters cast ballots, according to estimates from the United States Elections Project.
Data from the United States Elections Project also show that this year marked the highest turnout in a midterm election in more than 50 years.
Some dozen house races, as well as Senate seats in Florida and Arizona were still too close to call on Friday, with a Florida recount expected. Democrats seized the House majority by flipping at least 28 seats nationwide.
The Democrats could expand their House majority to as many as 35 new seats once all the votes are counted, which could take weeks in some cases.
Analyzing 417 House races that featured at least two candidates on the ballot, the AP determined that Democrats earned more than 51.4 million votes in competitive House races nationwide, or 52 percent, compared to 47.2 million votes cast, or 48 percent, for Republicans.
Voting experts noted that turnout exploded in states with big-ticket elections such as Florida, which featured high-profile races for Senate and governor. But even those states with lower-profile contests such as North Carolina, which featured only judicial races on the statewide ballot, saw similarly increased action. Voter participation rates jumped by around 10 points in both states.
Youth turnout, as defined by voters between 18 and 29, surged to a number not seen in a midterm election in a quarter century. Overall, 31 percent of eligible young people cast ballots, according to an analysis by the Center for Information and Research on Civil Learning and Engagement at Tufts University.
The Associated Press contributed to this report.
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