Sinclair Broadcast Group Inc.’s deal for Tribune Media Co. would give a broadcaster known for its conservative leanings fresh reach into leading media markets including New York, Los Angeles and Chicago.

Sinclair, which last month named a former aide to President Donald Trump as its chief political analyst and drew criticism for programming that benefited Trump and President George W. Bush during their campaigns, stands to gain stations in 42 cities and expand to a total of 108 communities.

The combined company would serve almost three-fourths of U.S. households, raising questions about the concentration of media voices.

“Media consolidation leaves consumers behind with fewer independent news sources in many media markets,” said Rep. Frank Pallone, the top Democrat on the Energy and Commerce Committee.

He blamed the policies of Federal Communications Commission Chairman Ajit Pai, a Republican chosen by Trump, for lowering barriers to broadcast mergers. The “announcement is disappointing, but should come as no surprise to anyone watching how Chairman Pai is running the FCC,” Pallone said.

Hunt Valley, Md.-based Sinclair will hold the largest group of affiliates for the ABC and Fox networks.

“Mega media #mergers in full swing,” Mignon Clyburn, the only Democrat on the FCC, said in a tweet. The $3.9 billion transaction will be reviewed by the agency, where the Republican majority recently eased merger rules to permit such a combination.

A combined Sinclair/Tribune would have 233 stations. Sinclair said it may sell some stations to comply with FCC ownership requirements and antitrust regulations. Regulators might demand that Sinclair sell stations in St. Louis; Salt Lake City, and Wilkes-Barre, Pa., Sinclair CEO Christopher Ripley said.

Chelsea Koski, a spokeswoman for Sinclair, didn’t return requests seeking a comment. FCC spokesman Neil Grace declined to comment.

Sinclair is credited with pioneering an aggressive tactic to expand from a single station in Baltimore in 1971. Under that strategy, Sinclair runs programming on the airwaves of a nearby station that retains its own FCC license. The stations can share front-office costs, too.

Pai’s Democratic predecessor, Tom Wheeler, in 2014 called the arrangements an “end-run around the one-to-a-market limitation.” Defenders, including Pai, say the arrangement helps cut costs, lets local stations afford news programming, and promotes station ownership by members of minority groups.

“Sinclair has shrewdly and effectively gamed the FCC’s ownership rules for many years,” said Andrew Jay Schwartzman, senior counselor at Georgetown University’s law school in Washington.

The expansion by Sinclair, which produces some national content for its local affiliates to use in newscasts, has led to speculation that the company could create a conservative-leaning alternative to Fox News if its relationship sours with the broadcaster.

Sinclair in April said it hired Boris Epshteyn, who had been a special assistant to Trump and adviser to his campaign.

In December, Trump’s son-in-law Jared Kushner — now a White House senior adviser — told business executives that the campaign struck a deal with Sinclair for better coverage, according to a report in Politico that cited unidentified sources. Sinclair said there was no such deal.