A sizable majority of Republicans think social media companies censor political speech, according to a new study from the Pew Research Center that quantifies perceptions of the Silicon Valley’s liberal bias.

Fully 85% of Republicans and right-leaning independents think social media sites intentionally censor political viewpoints, and a broad majority also think major technology companies as a whole support the views of liberals over conservatives.

The results of the Pew study, based surveys of 4,594 adults in the U.S. conducted from May 29 through June 11, are not surprising. Social media companies in general, and Facebook in particular, have become magnets for criticism by conservative commentators and lawmakers as these digital platforms play an increasingly important role in political discourse.

Allegations of liberal bias became a theme of Facebook CEO Mark Zuckerberg’s testimony this spring, when he appeared before a pair of Congressional hearings dealing with the Cambridge Analytica privacy scandal. Republican politicians, notably Sen. Ted Cruz of Texas, seized on the opportunity to grill Zuckerberg about the network’s approach to political speech.

“There are a great many Americans who I think are deeply concerned that Facebook and other tech companies are engaged in a pervasive pattern of bias and political censorship,” Cruz said, citing examples of conservative pages being shut down (he used the example of a Chick-Fil-A Appreciation Day page that was banned in 2012 after its COO criticized same-sex marriage).

Zuckerberg conceded that Silicon Valley is “an extremely left-leaning place,” but denied Facebook deliberately suppresses conservative viewpoints, saying the social network is “a platform for ideas.”

The Pew study notes that the public doesn’t object to online platforms regulating certain types of speech. For example, one 2017 survey found that the majority of Americans think these platforms have a responsibility to intervene when users engage in harassing behavior.

Although Republicans are more likely than Democrats to see anti-conservative leanings among major technology companies, those perceptions don’t translate to a desire for increased regulation.

Just over half of Democrats and those on the political left (57%) think these companies should be more heavily regulated, but only one-in-four Republicans see the need for greater government oversight.