WASHINGTON — Mark Zuckerberg’s social network in Washington is shrinking.

Bipartisan hostility against Facebook has been building for months, fueled by a series of privacy scandals, the site’s role in Russian meddling in the 2016 presidential campaign and accusations that Facebook crushes competitors.

Now, with the 2020 elections approaching, Democrats especially are homing in on the conduct of the social media giant and its refusal to fact-check political ads and remove false ones.

“When you’re the No. 1 monopoly, people are going to come after you,” says John Feehery, a veteran Republican communications strategist. The challenge for Democrats, as he sees it: “They’re facing a base that is very angry and restive. So they have to be much more aggressive in taking on corporations.”

Zuckerberg enjoyed a cozy relationship with the Obama administration. But in the face of growing public outrage, the co-founder of the upstart born under the motto “Move fast and break things” is learning the art of smoothing over and piecing back together.

His new strategy: a personal blitz featuring serial private meetings in Washington with key lawmakers of both parties and President Donald Trump; small, off-the-record dinners at his California home with conservative journalists and opinion makers; and the occasional public address or TV interview.

Addressing criticisms from Democratic lawmakers and civil rights groups over Facebook’s track record on fighting discrimination, Zuckerberg and Chief Operating Officer Sheryl Sandberg planned to host a dinner Monday night with civil rights leaders. The two executives want to hear the leaders’ “direct perspective and feedback,” the company said.

The Rev. Al Sharpton said last week that Zuckerberg would meet with him and others to discuss concerns such as Facebook’s handling of political messages. Misinformation on the platform can contribute to the suppression of voting by African Americans and other minorities, civil rights leaders say.

Zuckerberg has become lobbyist-in-chief for a tech giant that has about 60 people officially playing that role. The company spent an estimated $12.6 million on federal influencing last year.

The political ad issue hits close to home for Democrats. Facebook, as well as Twitter and Google, refused in September to remove a misleading video ad from Trump’s reelection campaign that targeted top-tier Democratic candidate Joe Biden. Sen. Elizabeth Warren, another top Democratic contender, chose to hit back by running her own ad and making it personal by falsely claiming that Zuckerberg had endorsed Trump for 2020.

Warren, who has called for breaking up Facebook and other tech giants, acknowledged the ad’s deliberate falsity to make her point.

Then came Zuckerberg’s speech last month at Georgetown University in which he promoted free expression as the foundation for Facebook’s refusal to take down content it deems newsworthy, even if the material violates company standards. The next week, during prickly questioning by Democratic lawmakers at a televised House hearing, Zuckerberg dug in on not fact-checking politicians’ speech and the handling of hate speech and potential incitements to violence.

“This really is not about money,” Zuckerberg insisted. “It is important that people can see for themselves what politicians are saying.” Facebook says political advertising accounts for less than half of 1 percent of its total revenue.

Separately from political advertising, Facebook has policies and improved technology that it says now enables it to more efficiently detect terrorist content in many languages. Following the mass shooting in New Zealand last spring, for example, Facebook now prohibits livestreaming by people who have violated rules covering organizations and individuals deemed dangerous and potentially violent.