The Democrats have captured another seat in the U.S. House of Representatives.
Political novice Andy Kim was declared the winner Wednesday from the third congressional district in New Jersey.
He defeated incumbent Republican Tom MacArthur.
Kim was a national security aide in the Obama White House. He is of Korean heritage and will be New Jersey's first Asian-American congressman.
Meanwhile, votes are still being counted more than a week after midterm elections for the House and Senate.
The day after the election, Trump boasted that "It was a big day yesterday. The Republican Party defied history to expand our Senate majority while significantly beating expectations in the House."
"It was very close to a complete victory," he trumpeted.
As results rolled in on election night, it appeared Republicans might add three or four seats to their current 51-49 Senate majority.
But a Republican lead for a contest in the southwestern state of Arizona collapsed, giving Democrat Kyrsten Sinema a seat that been held by Republicans for 30 years.
With Senate races in Florida and Mississippi yet to be decided, Republicans at most will add two seats to their majority.
In the House of Representatives, Democratic candidates are faring even better.
Democrats took back the House for the first time in eight years, and now have a 229-198 edge.
But Democrats appear poised to add to their majority come January in the new Congress, leading in six of the nine undecided races where absentee and mail-in ballots are still being counted, all in districts held by Republicans in the current Congress.
Incoming House Democratic leaders have vowed to immediately investigate the relationship between Trump's businesses and the federal government. They want to examine his tax returns that he has refused to release and plan to call on Trump officials to justify government policies they have adopted in the last two years of the administration.
While they have been in control of both chambers of Congress, Republican lawmakers rarely held hearings on Trump policies that presented the possibility of embarrassing the Republican president and his administration.
Trump is calling the nascent Democratic investigations "Presidential Harassment," and said the prospective probes have given a headache to national stock exchanges this week, leading to stock price losses.
Races for governorships in Georgia and Florida remain undecided amid late vote-counting and recounts, as is the key Senate race in Florida, where Governor Rick Scott, a Republican, is holding on to a 12,500-vote edge over the incumbent Democrat, Senator Bill Nelson. In the Florida race, local election officials are under a Thursday deadline to complete their recount of votes. The Mississippi Senate race is headed to a runoff election on November 27.
In the Florida contest, Scott and Nelson have filed competing lawsuits on various aspects of the vote counting. But the state agency overseeing elections has rejected claims by Scott and Trump of fraud, Despite the uncertainty of the outcome, Scott attended meetings in Washington for new lawmakers.
Trump has provided a running commentary on the Florida contest, at one point suggesting that Scott, along with Congressman Ron DeSantis, the Republican candidate looking to succeed him as governor ought to be declared the winners because they were ahead in the initial vote counting on election night.
"When will Bill Nelson concede in Florida?" Trump said on Twitter. "The characters running Broward and Palm Beach voting will not be able to 'find' enough votes, too much spotlight on them now!" Trump was referring to two Democratic strongholds along the Atlantic Ocean shoreline where Nelson, as more votes are counted, has cut into Scott's big-lead.
"Rick Scott was up by 50,000+ votes on Election Day, now they 'found' many votes and he is only up 15,000 votes," Trump complained. "'The Broward Effect.' How come they never find Republican votes?"
In another tweet, he sarcastically said, "Let’s blame the Russians and demand an immediate apology from President Putin!"