Rep. Haley Stevens of Michigan, a Democrat who lost her party's Senate primary to Abdul El-Sayed in August, endorsed Republican Mike Rogers on Sunday, two days before the election, in a battleground race that could help decide which party controls the Senate.

Stevens announced the decision in a video posted to social media after attending a Sunday service with Rogers at Perfecting Church in Detroit. "Our Democratic nominee for U.S. Senate, Abdul, said that I was no longer welcome in his campaign and that I should stay away, and he's right," she said. "And that's why I am endorsing Mike Rogers for the United States Senate today."

The seat is open because Democratic Sen. Gary Peters is not seeking another term. Democrats need a net gain of four Senate seats to take the majority, and a loss in Michigan would make that harder.

The endorsement capped days of open feuding between the former primary rivals. Stevens had pressed El-Sayed to condemn an outside group's ad that tied U.S. military aid to Israel to rising grocery prices, an ad she called antisemitic. El-Sayed said the ad "was not made by me" and that he disagreed with its contents, CBS News reported, but he also accused Stevens of being "intent on relitigating a primary that ended three months ago."

Other Democrats had invited Stevens to a Sunday unity event with El-Sayed and Rep. Jim Clyburn of South Carolina, part of an effort to put the primary fight behind the party. By Saturday, El-Sayed's campaign had asked her to stay away from its events. "I would rather not distract from the key issues of this campaign," El-Sayed said that day.

Rogers told reporters that Stevens called him Sunday morning and that the two decided to attend the service together. At the end of the call, he said, she reminded him that she was still a Democrat. "This is more a statement about standing together against hate and the future of this state and this country than it is anything else," Rogers said.

Stevens described the endorsement as a single exception rather than a change of party. "It is this one vote," she said, pointing to El-Sayed's association with Hasan Piker, who has appeared with El-Sayed at campaign events. She said she was not trying to harm the Democratic Party and called herself "still a very proud Democrat."

Democratic leaders rallied around El-Sayed on Sunday. Senate Minority Leader Chuck Schumer said Senate Democrats "are united in our support for Abdul El-Sayed" and called the endorsement a "despicable betrayal." Curtis Hertel, chair of the Michigan Democratic Party, wrote that Stevens "is not a current member of the Michigan Democratic Party, nor will she be in the future."

Members of her own staff broke with her, too. Stevens's longtime chief of staff, Justin German, resigned before the announcement, and her communications director, Logan Basch, also left, the Guardian reported, citing CNN. German said the team was "shocked and heartbroken" by her decision and was supporting El-Sayed.

El-Sayed dismissed the endorsement when he spoke with reporters outside a rally on Sunday, the same event from which Stevens had been disinvited. "At the end of the day, I actually don't think about Haley Stevens," he said. Voters who believe in standing up to hate, he added, would probably not want to support Rogers, President Trump or Vice President JD Vance.

Republicans welcomed the news. Trump, at a rally in Iowa, said he would "love her to join the Republican party," the Guardian reported, and he told reporters, "Nobody expected that." House Speaker Mike Johnson said he spoke with Stevens after she made the endorsement.

Stevens narrowly lost the August primary despite heavy support from the Senate Democrats' campaign arm. She gave El-Sayed a tepid endorsement after that race, and top Democrats brokered a truce between the two, but relations soured again in the campaign's final week.

On Sunday she said the choice was hers alone. "It's my personal and private decision," Stevens said. "It's a Michigan moment, and everyone is entitled to their opinion."