Mr Trump hailed "tremendous success" and an "incredible day" for his party in Tuesday's elections.
Plus, he said, Democrats have "nothing, zero", on him.
He mocked Republican candidates who distanced themselves from him, chided a reporter for asking a "racist question", and walked away from the lectern at one point, as an aide tried to wrest a microphone out of a reporter's hands.
One is that it takes a lot to swing white women Democratic. Tammy Baldwin held off a challenge from Republican Leah Vukmir, but her fellow Democrats Heidi Heitkamp of North Dakota and Claire McCaskill of Missouri were defeated by their Republican opponents.
Republicans found comfort in a series of Senate gains.
Mirroring their strong numerical gains in the nation's governorships, Democrats on Election Night seized control of seven legislative chambers. Bill Clinton lost 52 House seats in 1994 during his first midterm.
Republicans appeared to have won at least 56 seats in the House, while six other seats were captured by independent candidates and another eight seats were undecided because the results had either not yet been reported or were too close to call.
The president criticized Republican candidates who apparently did not support him enough and lost congressional seats in Tuesday's elections. "Two can play that game!"
Of Rep. Mike Coffman (R-Colo.), Trump said: "Too bad, Mike".
"Mia Love gave me no love", the president said. He said Barbara Comstock, who lost her suburban Virginia district, "didn't want to have any embrace". "Sorry about that, Mia", he said. "We have to make sure that we are advancing a common sense majority platform that America wants, and let's hope that we can bring Republicans aboard with us".
At the same time, Democrats must be careful not to overreach. They agree that a wall is necessary.More news: Democrat Andrew Gillum and Republican Ron DeSantis vote in Florida
Said Trump adviser Kellyanne Conway: "I don't know that there will be much of an appetite for Democrat lawmakers to spend all of their time, or most of their time or even a fraction of their time investigating, instigating, trying to impeach and subpoena people". Now the president will have no choice but to reach across the aisle to those in the House he has branded as "evil" and work with them. And in an interview with CNN colleague Anderson Cooper afterward, Mr. Acosta accused the White House of trying to intimidate the rest of the press corps.
In fact, he gave the once-and-future-speaker a shout-out: "I give her a great deal of credit for what she's done and what she's accomplished".
He singled out GOP Representatives Mike Coffman of Colorado, Mia Love of Utah, Barbara Comstock of Virginia, Carlos Curbelo of Florida, Peter Roskam of Illinois, Erik Paulsen of Minnesota, John Faso of NY and Bob Hugin, who challenged Senator Bob Menendez of New Jersey. "I think we can just barely even understand the doors that will open up for everyone".
"That's a racist question", he said, noting his relatively high approval rating among blacks.
But historical precedent suggests that an aggressive strategy targeting the president may backfire come 2020. Sen.
"The president is best when he is on the road talking directly to the American people, and I think last night's results demonstrate that", says Trump's former campaign manager Corey Lewandowski. Nonwhites, women and college graduates all tend to vote more Democratic. Perhaps with this in mind, Trump tweeted: "In all fairness, Nancy Pelosi deserves to be chosen Speaker of the House by the Democrats".
"To lose bc of POTUS & have him p*** on u", he said in a tweet. "Angers me to my core".
"Everybody understands that we have to choose our battles very carefully now", Raskin said.
"Women who had never run for anything stepped up to put their names on the ballot", she said. Erik Paulsen [of Minnesota] didn't want the embrace. If they do so, it will signal a "war-like posture", Trump said.
United States intelligence agencies have concluded the Russian government meddled in the 2016 election with social media posts meant to spread misinformation and sow discord, an accusation denied by Moscow.