Antitrust action is perhaps the most formidable tool in the incoming administration’s arsenal to rein in Silicon Valley.

President-elect Joe Biden is ascending to power after months of bipartisan momentum to expand antitrust enforcement against the tech industry and update existing competition laws for the digital era. Before even taking the oath of office, Biden and his staff are already under pressure to scale up that work.

The recent violence at the Capitol and its aftermath is adding fresh urgency, as tech platforms’ role in amplifying violent rhetoric highlights the industry’s broad power and influence over American democracy.

Democratic control of the White House and Congress could result in reforms to competition laws governing large tech companies’ business practices and even more litigation that could force breakups or significant structural changes at some of the world’s largest corporations.

“Basically, the Biden administration is inheriting a lot of momentum and a big opportunity to make online communications safe for democracy and fair in the commercial sphere,” said Sarah Miller, who leads the American Economic Liberties Project.

Biden and Vice President-elect Kamala D. Harris, both moderate Democrats, are not the most likely politicians to take on power in Silicon Valley. They were not as aggressive as some of their more liberal peers, such as Sens. Elizabeth Warren (D-Mass.) and Bernie Sanders (I-Vt.), in calling to break up specific tech giants during the Democratic presidential primary.

Biden has said little specifically about how he intends to address antitrust issues in Silicon Valley, but he promised throughout his candidacy that he would take on growing economic concentration and monopoly power.

Consumer advocates and liberal Democrats want the Federal Trade Commission (FTC) and the Justice Department under Biden to be significantly tougher on the tech giants than they were during the Obama presidency. Facebook, Google and Amazon did not have a single merger blocked between 2009 and 2016.

And many expect these agencies will be as the tech industry’s fortunes in Washington have significantly dwindled in the intervening years. The incoming officials at the Justice Department and the FTC will inherit a pair of federal antitrust lawsuits filed last year against Facebook and Google that are widely expected to proceed after the transition.

Both Democrats at the FTC supported a lawsuit against Facebook by the agency, which argued that the company is an illegal monopoly that should potentially be broken up. The Justice Department also filed a lawsuit in the fall against Google. The suit received broad bipartisan support.

But Biden is under pressure to expand this litigation. A recent report from the American Economic Liberties Project, an anti-monopoly group led by a member of Biden’s transition team, called on the incoming Justice Department to commit to “seeking a Google breakup.” The department’s lawsuit currently focuses on the power the company exerts over search, and the group wants it to challenge the company’s position in travel, maps and the App Store.

The group also called on the FTC to bring an antitrust case against Amazon, which has faced scrutiny over its treatment of third-party sellers. (Amazon chief executive Jeff Bezos owns The Washington Post.)

Antitrust is also increasingly a priority in Congress. Now that Democrats will control the House and the Senate, they will be able to use their powerful perches to call in executives to testify about competition in the industry. Last year, House Democrats led a grilling of the chief executives of Apple, Amazon, Facebook and Google on these issues.

Biden’s campaign said last year that he plans to work with Rep. David N. Cicilline (D-R.I.), who led an investigation that found that Amazon, Apple, Facebook and Google engaged in anti-competitive tactics. The report recommended broad changes to laws that would punish big companies, such as making it illegal for Amazon and Google to give greater preference to their own products over competitors’ merchandise on their platforms. The recommendations also included expanding federal regulators’ powers to block future tech mergers.

Those recommendations could serve as a blueprint for legislation in the coming months. However, it remains to be seen how much of a priority antitrust policy will be in the new Congress, as lawmakers also grapple with the coronavirus pandemic, the economic crisis and the second impeachment of President Trump. Cicilline, who declined to comment for this article, is one of the managers of the impeachment process.

“There’s an extent to which this is part of those crises,” said Charlotte Slaiman, competition policy counsel at the consumer group Public Knowledge. “The misinformation that is spreading on social media is making it harder for us to contain the coronavirus pandemic. It is making it harder for our democratic processes to function properly. I think this still absolutely needs to be a high priority with those other concerns.”