A wave of anger over Trump's policies, particularly the US-Iran war's role in pushing the cost of living higher, helped Democrats take the Senate, where they flipped seats in deeply Republican states for a majority of at least 54-44, and the House of Representatives, where they gained at least 25 seats.
But Trump said on Wednesday the Iran war has been worth the losses, if it meant it stopped Tehran from "having a nuclear weapon".
"The Iran thing we had to do, and we continue to do it," he told reporters.
"I can tell you that as far as that war is concerned, I would have done nothing different," Trump said.
Trump also again said that if he had been on the ballot, he believed "we would have won."
"But they just, you couldn't transfer that love. There was such love at those rallies, it was incredible and we weren't able to transfer the love to candidates," he said
It will be the first time that Trump, a Republican who also held the White House from 2017 to 2021, has had to contend with a Democratic-controlled Congress.
"The American people have connected that corruption into the adverse impact of the policies that have taken place over the last two years," House Democratic Leader Hakeem Jeffries told MS NOW on Wednesday, promising to "make sure that wrongdoers are being held accountable."
Trump, meanwhile, posted an image on social media of one of his signature red "Make America Great Again" baseball caps with the usual slogan replaced with the word "VETO", a reminder that Democrats will be limited in their ability to legislate without his support.
Top Senate Republican John Thune, a veteran congressman not generally regarded as a firebrand, signaled that his caucus was not yet ready to look to a future beyond Trump.
"Senate Republicans will not stand idly by as the far-left, socialist wing of the Democrat Party attempts to unwind everything we've done," Thune, of South Dakota, said in a statement.
"Thankfully, we still have President Trump in the White House, and we'll work with him to stop the worst impulses of Democrat extremism."
Trump had cast the midterm elections as a referendum on the first half of his second four-year stint in the White House, repeatedly urging his Republican base to "pretend I'm on the ballot," a message that Democratic Party leaders were happy to amplify.
The result: voters in conservative strongholds who had propelled the president to his second term in office just two years ago swung dramatically toward Democrats, fueled by deep frustration over the unpopular war with Iran, anxiety over the high cost of living and anger at Trump's stewardship of the country.
In Texas, the biggest Republican-led state before Tuesday, Democrats ended a decades-long losing streak in seismic fashion, winning their first Senate seat there since 1988 and ousting three-term Governor Greg Abbott.
Kansas elected its first Democratic senator since the Great Depression nearly a century ago, and in South Carolina, a state that Trump carried by nearly 18 points in 2024, Democrats turned aside his hand-picked Senate candidate.
Once seated in January, Democrats are expected to use their power to investigate Trump's administration, family and allies and demand concessions on major legislation. However, until then, Republicans hold the reins.
Trump, who is barred by the US Constitution from seeking a third term, has exercised an iron grip on his party for most of the last decade. He congratulated Democrats for doing "a good job," in uncharacteristically conciliatory media interviews overnight.
He acknowledged the war with Iran had played a role in his party's losses but stood by his decision. He also said he would work with Democrats on issues such as immigration, though he threatened to veto any "insane" bills they passed.
Abdul El-Sayed, a Democrat from the party's rising left wing, won Michigan's open Senate seat, becoming the first Muslim elected to the chamber. He defeated Mike Rogers, a former congressman and FBI agent, who entered the race with Trump's backing and sought to falsely portray El-Sayed, an Egyptian American born in Michigan, as a religious extremist.
"You chose hate, and Michigan chose hope," El-Sayed told cheering supporters on Tuesday night, referring to Rogers.
