WASHINGTON – While touting Republican wins in the Senate, President Donald Trump spent the post-election Wednesday morning threatening to investigate Democrats who won control of the House and are now threatening to investigate him.

"If the Democrats think they are going to waste Taxpayer Money investigating us at the House level, then we will likewise be forced to consider investigating them for all of the leaks of Classified Information, and much else, at the Senate level," Trump said during an early morning tweet storm.

"Two can play that game!" he added.

The president also scheduled a news conference Wednesday to discuss what he called "our success in the Midterms!"

Democrats, meanwhile, began planning their takeover of the House in January, including increased oversight of Trump and his administration.

“We'll fill in the gaps on the Russia investigations," said Rep. Eric Swalwell, D-California, a member of the House Intelligence Committee, speaking on NBC's "Today" show. "The American people will see his (Trump's) tax returns, not because of any voyeuristic interest, but because they should know if he is corrupt."

In a series of other early-morning tweets, Trump took credit for GOP victories in close races on Election Day while blaming losses on Republicans who shunned his support.

"Those that worked with me in this incredible Midterm Election, embracing certain policies and principles, did very well," Trump said in one tweet. "Those that did not, say goodbye!"

Trump raised questions about the Russia investigation by Special Counsel Robert Mueller, citing an NBC News exit poll that found slightly more voters opposed the probe than support it. The tweet marked the first time Trump has tweeted about the investigation in weeks.

"You mean they are finally beginning to understand what a disgusting Witch Hunt, led by 17 Angry Democrats, is all about!" Trump wrote.

He also attacked the news media, saying in one post that any "pundits or talking heads" who do not give the Trump team "proper credit for this great Midterm Election" are just "FAKE NEWS!"

The president's news conference is set for 11:30 a.m. EST at the White House.

Newly empowered House Democrats said they would pursue new health and jobs legislation along with increased oversight of the Trump administration.

"We will get to work on Day One creating jobs rebuilding our infrastructure, bringing down the cost of prescription drugs and cracking down on any politician who abuses their public office," said Rep. David Cicilline, D-Rhode Island, co-chair of the Democratic Policy and Communications Committee.

Democrats said their targets range from accused ethical lapses by members of the Cabinet to allegations that Trump's campaign worked with Russian hackers to influence the 2016 presidential election.

In his NBC interview, Swalwell said, "We will look at the cashing in of access to the Oval Office and that has been concerning and his financial entanglements overseas.”

Trumpo was not specific about his threat to counter-investigate the Democrats. In recent weeks, he has accused them of improperly leaking information about then-Supreme Court nominee Brett Kavanaugh.

Some critics said Trump's threat doesn't bode well for working together on legislation.

Matthew Miller, a spokesman for the Justice Department under President Barack Obama, noted that Trump is thinking of dismissing Attorney General Jeff Sessions. Amid those reports, Miller tweeted: "Trump threatens criminal investigations of his political critics. Things are going just as expected."

The president didn't directly address the outcome that represents a seismic shift in national politics: the Democratic takeover of the House of Representatives. Democrats picked up dozens of seats on Tuesday, including many in districts Trump won in 2016.

Instead, on Twitter, he played up Republican victories.

Trump posted a quote from supporter and writer Ben Stein suggesting the results showed the president has "magic coming out of his ears" because the GOP expanded its Senate majority by winning races in Indiana, North Dakota and Missouri.

Minutes later, Trump tweeted a quote he evidently heard from a Fox Business Network anchor indicating his standing with Republicans in Congress should increase because of the blitz of campaigning he conducted in the run-up to Tuesday's election. The anchor wrote that successful Republicans owed Trump their careers.

"Thanks," Trump added in a tweet. "I agree!"

Trump was engaging in a well-worn tradition for presidents to reflect on and spin the outcome of midterms – an effort all but certain to continue later Wednesday. Past presidents have acknowledged their losses in particularly colorful language.

When Republicans lost 30 seats and control of the House of Representatives in 2006, President George W. Bush memorably summed up the results of his second midterm election in a single word: It was, the president told reporters, a “thumpin’.”

In a news conference after the 2010 election, in which Democrats lost a whopping 63 seats, President Barack Obama acknowledged that his relationship with voters had gotten “rockier” and elicited a laugh by describing the Republican wave as a “shellacking.”

The president did spend the post-election hours calling various winners, including House Democratic Leader Nancy Pelosi of California. He also spoke with Senate Democratic leader Chuck Schumer of New York.

In something of a backhanded compliment, Trump tweeted that Pelosi deserves to be chosen House Speaker by her fellow Democrats, some of whom have criticized her leadership. "If they give her a hard time, perhaps we will add some Republican votes," Trump said. "She has earned this great honor!"

The president also called to congratulate incoming Republican senators, including Rick Scott of Florida, Kevin Cramer of North Dakota and Josh Hawley of Missouri.

Trump officials said they have prepared for the prospect of a Democratic House. One strategy, they said, would be to focus on items handled by the Republican-run Senate, a list that includes trade agreements and judicial nominations.

Presidential counselor Kellyanne Conway said Trump managed to avoid an Obama-like "shellacking," and now he will try to work with Democrats on issues of common interest like immigration and infrastructure.

As for House investigations of Trump and his administration, Conway said they will deal with them as they come up.

She also hinted at legal challenges to House subpoenas.

Asked what would happen, for example, if the House Democrats seek Trump’s tax returns, Conway said: “We’ll talk to the lawyers about that – we’ll see what happens.”

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