A Democratic majority in both chambers could create several challenges for Trump. Here are the key areas where the change in political control could make a difference.
1. Passing new laws could become difficult
The most immediate impact will be on Trump's ability to pass legislation.
Under the US system, a bill generally needs approval from both the House of Representatives and the Senate before it can reach the President. With Democrats controlling both chambers, proposals related to taxation, government spending, healthcare and other domestic priorities could face strong opposition.
Democrats could block Republican-backed bills or refuse to approve legislation that does not meet their demands. They could also introduce their own proposals, although getting them through the Senate may prove difficult.
This is where the Senate's filibuster becomes important.
The filibuster allows senators to prolong debate and delay or prevent a vote on legislation. In most cases, 60 votes are needed to end debate through a procedure known as cloture.
Even with control of the Senate, Democrats may not have enough votes to overcome this hurdle on their own. They will therefore need support from some Republicans to pass many major bills.
2. Trump could face greater congressional investigations
Control of the House will give Democrats an important advantage: the power to lead congressional committees.
These committees can hold hearings, seek documents, summon witnesses and use subpoenas as part of investigations into government activities.
Democrats have already indicated that they want to examine several issues involving Trump, his family and his administration.
Potential areas of scrutiny include:
- The business and cryptocurrency ventures of Trump and his family.
- Financial dealings involving Trump's son Donald Trump Jr. and son-in-law Jared Kushner.
- Funding and donations connected to the proposed White House ballroom project.
- The administration's handling of documents related to convicted sex offender Jeffrey Epstein.
- Defence contracts and government funding involving companies linked to the Trump family.
The proposed investigations could place Trump's business interests and administration under renewed scrutiny.
However, congressional investigations have limits. Congress can investigate alleged wrongdoing, demand information and refer matters to law enforcement, but it cannot itself prosecute individuals or impose criminal sentences. Any criminal charges would have to be pursued through the appropriate law enforcement and judicial processes.
3. Could Democrats try to impeach Trump again?
Another possibility is a renewed attempt to impeach Trump.
The President has already faced impeachment twice during his first term in office. On both occasions, the House of Representatives approved articles of impeachment, but the Senate did not secure the votes required to convict him.
With Democrats now controlling the House, the possibility of another impeachment process could return to the political debate.
The US Constitution gives the House the power to impeach a President. A simple majority is sufficient to approve articles of impeachment, meaning Democrats would not necessarily need Republican support to initiate the process.
However, impeachment does not automatically remove a President from office.
Once the House approves the articles, the matter moves to the Senate for a trial. Conviction requires the support of two-thirds of senators present. Only after conviction can the President be removed from office.
Given the high voting threshold, Democrats would need considerable Republican support to remove Trump through this process.
In short, a Democratic-controlled House could impeach Trump, but it cannot remove him from office on its own.
4. Presidential appointments could face delays
The Senate has an important constitutional responsibility: confirming senior government appointments.
These include federal judges, Supreme Court nominees, ambassadors and senior officials in the administration.
With Democrats controlling the Senate, Trump's choices for important government positions could face tougher questioning, delays or rejection.
This could make it harder for the President to fill key positions and influence the federal judiciary. Judicial appointments are particularly important because federal judges, including Supreme Court justices, can shape American law and policy for decades.
The Senate's confirmation powers will therefore become an important source of political pressure on the Trump administration.
5. Budget battles could trigger a government shutdown
Another major area of conflict could be government spending.
Congress controls federal spending and must approve funding for government departments and programmes. A Democratic majority could refuse to support funding proposals that include Trump's priorities unless the administration agrees to certain conditions.
This could lead to prolonged negotiations between the White House and Congress.
If lawmakers fail to reach an agreement on government funding before the deadline, parts of the federal government could shut down.
Budget disagreements could also involve the debt ceiling, which determines how much the government can borrow to meet its existing financial obligations.
Such disputes could become a major political challenge for Trump during the remaining years of his presidency.
