Despite Democrat Elissa Slotkin’s victory in Michigan’s open U.S. Senate seat, the national red wave on Tuesday ran counter to Democratic hopes, as Republicans took over the Senate majority by securing at least four seats in Ohio, Pennsylvania, Montana and West Virginia. Preliminary figures also indicate they may gain an additional seat in Arizona or Nevada.

Slotkin, currently a U.S. Representative for Michigan, narrowly defeated former Republican U.S. Rep. Mike Rogers, leading by less than half a percentage point — around 21,000 votes — despite record-breaking spending in her campaign. Slotkin garnered approximately 2.71 million votes (48.7 percent) compared to Rogers’ 2.69 million (48.3 percent), dashing Republican hopes to win one of Michigan’s two Senate seats for the first time since 1994, when Spencer Abraham defeated Democrat Bob Carr. Slotkin will succeed current Democratic Senator Debbie Stabenow, who decided not to seek a fifth six-year term.

Majority shift

Nationally, the Republican Party regained control of the U.S. Senate after flipping Senate seats in West Virginia, Montana, Ohio and Pennsylvania from Democrats, boosting their share of Senate seats from 49 to 53 out of 100, with the possibility of securing one of the seats in Arizona or Nevada pending final results. Republicans needed only one additional seat to secure a majority due to Donald Trump’s presidential win, which allows Vice President-elect J.D. Vance to serve as the tie-breaking vote in the Senate according to the U.S. Constitution.

Republicans achieved an early victory in the race to control Congress when West Virginia Governor Jim Justice easily won the seat of moderate Democratic Senator Joe Manchin, who opted not to run for re-election. In Ohio, Republican candidate Bernie Moreno unseated incumbent Democratic Senator Sherrod Brown by about 111,000 votes. In Pennsylvania, current Democratic Senator Bob Casey lost to Republican rival Dave McCormick by around 31,000 votes. In Montana, Democratic Senator Jon Tester lost by approximately 45,000 votes to Republican Tim Sheehy.

As of this report, Senate races in Arizona and Nevada remain undecided, potentially increasing the Republican majority beyond 53 seats.