Republicans seized control of the Senate in Tuesday’s voting, picking up at least two Democratic seats and protecting their own embattled lawmakers to end four years of Democratic control.

Senator Sherrod Brown, the Ohio Democrat who party leaders hoped could overcome the Republican tide in his solidly red state, was defeated in his bid for a fourth term by the luxury car dealer Bernie Moreno. Brown’s loss came after governor Jim Justice of West Virginia easily won the slot opened up by the retirement of Senator Joe Manchin III, who served most of his career in the Senate as a Democrat before becoming an independent this year.

The two losses reversed the 51-to-49 majority held by Democrats after Republican Senator Deb Fischer of Nebraska held off an unexpectedly steep challenge from Dan Osborn, who ran as an independent. Republicans, whose campaigns appeared to be benefiting from former President Donald J. Trump’s strength in battleground states, could pad their new majority given very tight races in Wisconsin, Pennsylvania, Michigan and Nevada, and a Republican edge in Montana.

In the other congressional battle, control of the House remained up for grabs as Republicans and Democrats grappled for advantage in about two dozen competitive races in battleground states and on the two coasts that remained too close to call. Democrats picked up a pair of seats in New York but still needed to defend several incumbents and pick off a number of other Republicans to win control from the Republican, which currently holds a four-seat majority.

It could be days before enough results, especially in several critical races in California, are known to declare a winner.

Top Senate Republicans cheered their success, which will give them a leading role in shaping policy in the nation’s capital next year.

“Voters are trusting Senate Republicans with an extraordinary opportunity,” said Senator John Barrasso, the No. 3 Republican, who was re-elected in his own race in Wyoming. “As a new Republican Senate majority, our focus will be to take on an agenda that reflects America’s priorities — lower prices, less spending, secure borders and American energy dominance.”

The new majority will be under new leadership for the first time in 18 years since Senator Mitch McConnell, Republican of Kentucky, is stepping down from the top post he has held since 2007. Republican senators are scheduled to choose their new leaders next week as they prepare to assume chairmanships of committees that have been run by Democrats since 2021.

The loss of the majority led by Senator Chuck Schumer, Democrat of New York, was a major disappointment for Democrats who had hoped to navigate a narrow path to remaining in power. But the task of defending seats in states Trump had repeatedly carried proved too difficult.

House hopes

Representative Mike Lawler, one of the nation’s most endangered Republican incumbents, won a second term, holding onto a suburban New York district that is typically tilted towards Democrats.

His victory over Mondaire Jones, a former Democratic congressman, buoyed Republicans’ hopes of holding the House majority.

Reuters, AP