The significant gains by the Democrats in the midterm election could mean the party launches probes on Trump.
The Democrats secured major gains in the US midterm elections on Wednesday, leading to President Donald Trump threatening to fight back if the Democrats launch probes against him.
In a sign of mounting pressure on the president, Trump almost immediately rearranged his cabinet when Attorney General Jeff Sessions resigned at Trump's request.
Sessions was an early supporter of Trump but fell foul of the president after he removed himself from an investigation into Russian meddling in the 2016 presidential campaign.
His departure could be the first of a long line of high-profile exits as Trump reshapes his team for the 2020 election, especially since the midterm vote which could dramatically change the fate of the White House in the next two years.
The Democrats regained control of the House of Representatives in winning more than 23 seats to win a majority in the 435 seat House. It is their first majority in eight years.
The party adopted a trio of policy goals which proved favourable: reducing health care costs, creating jobs through infrastructure investment, and offering a reform package to clean up politics.
The Democrats also picked up key Republican seats in Colorado, Florida, Kansas, Minnesota, New York, Pennsylvania and Virginia.
However, some other key seats, including in Arizona and Florida remained too close to call.
A record number of women and candidates of colour and LGBT people also won races across the country.
That result now means the Democrats will now head the House of Committees that can probe Trump's tax returns, which the president has refused to hand over since he became a candidate.
The party could also probe any possible business conflicts of interest and links between his 2016 presidential campaign and Russia, which is currently being investigated by attorney Robert Mueller.
However, the Democrats stopped short of regaining full control. The party did not secure a Senate majority, which could have given the Democrats powers to block any further Supreme Court nominations and open more probes into the president.
Trump said: “They can play that game, but we can play it better, because we have a thing called the United States Senate,” he said referring to GOP control of the upper chamber. “ . . . I think I’m better at that game than they are, actually, but we’ll find out.”
The president also warned of a “warlike posture” in Washington if Democrats investigated him.
However, the result could lead to a bipartisanship between the GOP and Democrats. Trump said he was willing to work with his opponents on key priorities such as restoring trade with China and infrastructure improvements.
A relationship could all depend on who is named as the House speaker. House Minority Leader Nancy Pelosi is the front-runner for the job.
Despite having demonised Pelosi on the campaign trail, Trump threw his support behind her on Wednesday.
“I think she deserves it,” he told reporters. “She’s fought long and hard. She’s a very capable person.”