President Donald Trump takes questions as he speaks during a news conference in the East Room of the White House, Nov. 7, 2018, in Washington.
President Donald Trump takes questions as he speaks during a news conference in the East Room of the White House, Nov. 7, 2018, in Washington.

U.S. President Donald Trump is boasting of "a Very Big Win" in Tuesday's national congressional elections, after Republicans strengthened their hold on the Senate, even as Democrats took control of the House of Representatives for the first time in eight years.

"Those that worked with me in this incredible Midterm Election, embracing certain policies and principles, did very well," Trump said on Twitter early Wednesday ahead of his White House news conference on the election.  "Those that did not, say goodbye! Yesterday was such a very Big Win, and all under the pressure of a Nasty and Hostile Media!"

But at a contentious White House news conference, Trump sparred with reporters over his assessment of the election. He contended that Republicans "defied history" by picking up several Senate seats in ousting incumbent Democratic lawmakers during the first national congressional elections after his 2016 presidential election.

"History will see what a good job we did in getting people over the finish line," Trump said, noting that nine of the 11 candidates he campaigned for in the last week won their contests.

WATCH: Midterm Aftermath Could Lead to Cooperation and Conflict


The results, however, make it more difficult for Trump to win approval for his legislative initiatives. House Democrats are also vowing to launch numerous investigations of Trump's finances and his administration's policies, which the U.S. leader said would be matched with Senate Republican probes of Democrats.

Trump said he could embrace legislative compromises with Democrats, but said that if Democrats carry out an array of investigations, "I think I'm better at that game than they are."

Rep. Jacky Rosen, D-Nev., center, celebrates at a Democratic election night party after wining a Senate seat, Nov. 7, 2018, in Las Vegas.
Democrats Retake House, Creating Divided Congress
Midterm result seen as a partial rebuke of President Donald Trump

Trump called House Democratic leader Nancy Pelosi to congratulate her on the Democratic takeover in the House.  He said Democratic lawmakers, some of whom have said the party needs new and younger leadership, should again make her the House speaker, the top position in the chamber and second in line to the presidency.

The 78-year-old Pelosi was the first woman to be House speaker, from 2007 to 2011, when Democrats last held a House majority.

House Minority Leader Nancy Pelosi of Calif., righ
House Minority Leader Nancy Pelosi of Calif., right, steps away from the podium as House Minority Whip Steny Hoyer, D-Md., makes the thumbs up sign, after Pelosi spoke about Democratic gains in the House of Representatives to a crowd of Democratic supporters during an election night returns event at the Hyatt Regency Hotel, on Tuesday, Nov. 6, 2018, in Washington.

"In all fairness, Nancy Pelosi deserves to be chosen Speaker of the House by the Democrats," Trump said.  "If they give her a hard time, perhaps we will add some Republican votes.  She has earned this great honor!"

Trump appeared determined to take credit for Republican victories, tweeting, "To any of the pundits or talking heads that do not give us proper credit for this great Midterm Election, just remember two words - FAKE NEWS!"

The split congressional outcome, which independent pollsters and analysts had been predicting for weeks, serves as at least a partial rebuke of Trump, who staged 11 political rallies in eight states in the last week of the campaign, repeatedly telling his most fervent Republican supporters the election was essentially a referendum on his 22-month presidency.

Pelosi, in claiming a House victory for Democrats, said the election was more than about Democrats and Republicans.  Rather, she said, "It's about restoring constitutional checks and balances to the Trump administration."

In the House, legislative committees have strong investigatory powers.  Some Democrats have suggested they will investigate whether Trump has any personal or financial conflicts of interest by demanding to see his tax returns, which he has refused to release, and look into his financial and business interests, as well as his 2016 presidential election campaign's alleged ties to Russia.

Some Democrats have called for Trump's impeachment and are waiting to see what special counsel Robert Mueller's investigation concludes about the 2016 election, and whether Trump, as president, obstructed justice by trying to thwart the probe, University of Virginia analyst Larry Sabato said,  "Big legislation with an ideological tint, left or right, won't pass for the next two years.  Democrats now have the power of subpoena so Trump and his administration can expect to be investigated rather than protected by the House."

But by retaining control of the Senate, Republicans will preserve the ability to confirm Trump's judicial nominations and other key appointments.  The Republican-led Senate also could prevent Congress from removing Trump from office, if the Democratic-controlled House decides to move forward with impeachment proceedings.

Enthusiasm and large turnout

Though votes are still being counted in 21 congressional districts, Democrats are projected to pick up more than 30 seats in the House, more than the 23 seats they needed to claim the majority.  That is consistent with many pre-election polls.

Democrats drew largely on a coalition of minority voters, young people and those in urban and suburban swing districts, many of whom were upset over Trump's style of leadership and harsh language about immigrants and minorities.

"The demographic crisis has finally hit," says Evan Siegfried, a Republican analyst.  "And in a way that is brutal and is decimating the Republican Party."

Though polls had suggested healthcare and the economy were main issues for voters, Trump was never far from voters' minds.

A CNN national exit poll suggested 55 percent of voters disapprove of Trump's performance while 44 percent approve of it.  Moreover, 56 percent of those surveyed believe the country is on the wrong track and only 41 percent said it was on the right track.

However, Republicans secured at least the 51 to 49 seat majority they hold now in the Senate and are expected to add a few more seats once the final results are in.

The U.S. Capitol Building in Washington is shrouded in fog early on Election Day, Nov. 6, 2018.
Thoughts on the US Congressional Elections
As Election Day unfolds Tuesday in the United States, prominent American political figures are offering their thoughts on the national elections that will determine who controls Congress for the next two years as the country inches closer to the 2020 presidential election.Here is what some of them said:Former Vice President Joe Biden, possibly a Democratic challenger to Republican President Donald Trump in the next race for the White House, said he would be "dumbfounded" if Democrats do not win back…

The White House said early Wednesday that Trump called Senate Majority Leader Mitch McConnell "to congratulate him on the historic Senate gains."

Precincts across the country reported strong voter numbers for a midterm election.

The New York Times and Michael McDonald of the United States Election Project both estimated national turnout of at least 111 million, far surpassing the 83 million people who voted in the 2014 midterms.

Elizabeth Cherneff contributed to this report.