The Democrats protected several vulnerable chambers as well, including the Connecticut House, the Delaware Senate and the Maine House.
Blue-collar voters and rural America embraced his aggressive talk and stances.
Two other key Democratic lawmakers, Elijah Cummings of Maryland, who will nearly certainly head the House Oversight Committee, and Adam Schiff of the Intelligence Committee, have both called for new oversight of Trump and his administration, probes often blocked by majority Republicans in the past two years. This happened in 2010 when a Democratic Congress passed the Affordable Care Act - Obamacare - with no Republican votes, and it happened again a year ago when the current Congress passed President Donald Trump's so-called tax cuts with only Republican support.
Mr Trump's remarks on party dynamics came after Senate majority leader Mitch McConnell said he had spoken with House Democratic leader Nancy Pelosi about how they might "find a way forward" in a divided Congress next year.
Ms Pelosi - who is set to become speaker, a position she held from 2007 to 2011 - told supporters: "Today is more than about Democrats and Republicans".
Another important trend from this year's exits (and any year's) is how gender interacts with race and education.
The newly elected Republican opposes Medicaid expansion; South Dakota is one of 19 states to refuse the expansion, which would cover more than 40,000 of the state's most vulnerable residents.
Record diversity on the ballot may have helped drive turnout.
All 435 seats in the U.S. House were up for re-election, although fewer than 90 were considered competitive. If Pelosi moves forward with her bid for speaker, those 20 members will have to ask themselves whether they want to make her vulnerable to a challenge on the House floor, leaving Democrats squabbling just when they've gotten the majority back after almost a decade in the wilderness. Blackburn will be the first female senator to represent her state. Roskam kept his distance from Trump in a district that went for Hillary Clinton over Trump in 2016.
The latter emphasise Trump's surprisingly protectionist economic rhetoric - once unthinkable from a Republican - that railed against a system controlled by global elites to the detriment of the working Americans who've watched their jobs disappear.More news: Jim Acosta Physically Grabs Microphone Away From Female Staffer
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In Kansas, Democrat Sharice Davids beat a GOP incumbent to become the first gay Native American woman elected to the House. But in Kentucky, one of the top Democratic recruits, retired Marine fighter pilot Amy McGrath, lost her bid to oust to three-term Rep. Andy Barr.
Trump himself lauded the Republican electoral gains, saying on Twitter: "Tremendous success tonight".
Republican Congressman Ron DeSantis claimed the governorship over Democrat Andrew Gillum, the Mayor of Tallahassee, by less than a point, while the Senate contest between Democratic Senator Bill Nelson and Republican Governor Rick Scott is heading for a recount.
Some hurt worse than others.
As one Democrat put it: "We have not figured out Florida, which is a problem".
Trump encouraged voters to view the 2018 midterms as a referendum on his leadership, pointing proudly to the surging economy at recent rallies. "It's not just that many of them are women or people of color - many of them are progressives who won their elections demanding Medicare for All [government-backed health insurance], demanding raising the minimum wage to $15 an hour, and making public colleges and universities tuition free".
He bet big on a xenophobic closing message, warning of an immigrant "invasion" that promised to spread violent crime and drugs across the nation.
McConnell eschewed further attempts to get him to respond to heated presidential rhetoric, refusing to call the migrant caravan - still hundreds of miles from the southern US border - a "crisis", as Trump did in high profile campaign rallies created to turn out the GOP base. Kobach had built a national profile as an advocate of tough immigration policies and strict voter photo ID laws. AP VoteCast also showed a majority of voters considered Trump a factor in their votes.
The number of seats required to take the majority is 218.
There are a half dozen House committees that have the power to investigate Trump - Intelligence, Oversight, Ways and Means, and Judiciary, among others.
"And in New Jersey, I think he could have done well but didn't turn out too good". Cory Booker, California Sen.