WASHINGTON— The results of the U.S. midterm elections were not yet clear enough Wednesday to know which party will control Congress from January, although local media continues to bet on the Republicans retaking the House of Representatives by a narrower margin than expected.

Control of the Senate has come down to a few races, with Democrats scoring a crucial win in Pennsylvania by flipping a seat previously held by a Republican. Georgia, another key state, is heading to a runoff slated for Dec. 6, according to U.S. media.

The extremely tight race in the House came as a surprise, as the Democratic Party was seen as facing strong headwinds due to voter frustration with high inflation and the sagging popularity of President Joe Biden.

While the midterms usually serve as a referendum on the incumbent leader, Biden sought to make Tuesday’s elections about his predecessor Donald Trump and his “extremist” wing of the Republican Party, warning that they threaten democracy and basic rights, including through their denial of the results of the 2020 presidential race.

The Democrats also campaigned for abortion access, banking on the strong public backlash triggered by a Supreme Court decision in June that overturned a landmark 1973 ruling guaranteeing the constitutional right to abortion.

In Tuesday’s contests, all 435 seats in the House and about one-third of the 100 seats in the Senate were on the ballot. In addition, 36 out of 50 states had races for governor.

The Democratic Party currently holds a slim majority in the House. The Senate is evenly divided, but Democrats hold the majority due to the tie-breaking vote of Vice President Kamala Harris.

In an election event that took place in the early hours of Wednesday, House Republican leader Kevin McCarthy, who is likely to become speaker of the chamber if his party takes control, said, “It is clear that we are going to take the House back.”

A Republican-controlled House would likely dampen the prospects of the remaining two years of Biden’s presidency, as the chamber could block the passage of big spending bills and ramp up oversight of the administration.

A Republican takeover of the Senate would be even more damaging to Biden, as the chamber also has the power to block the president’s Cabinet picks and judicial nominees.

The races in Arizona, Georgia and Nevada are now closely watched as the outcomes will decide which party takes control of the Senate.

In Pennsylvania, Democrat John Fetterman, the eastern state’s lieutenant governor known for his tattoos and trademark hoodies, beat Republican TV personality Mehmet Oz, who was backed by Trump.

In the hotly contested race in the southern state of Georgia, a runoff is expected between Democratic Senator Raphael Warnock and Republican former college football star Herschel Walker, endorsed by Trump.

Election workers sort ballots at a Maricopa County facility in Phoenix, Arizona, on Nov. 9, 2022, a day after the U.S. midterm elections. (Getty/Kyodo)