Most Americans are big fans of local news, and so is "Last Week Tonight" host John Oliver.

"Local news fills an important role—finding stories that the national news is missing," Oliver opened on Sunday, highlighting several stories he's cited on his show.

"In fact," he added. "A Pew study last year found that local news is trusted more than national news."

That could all change with the new Sinclair-Tribune deal announced in early May, a nearly $4 billion media merger still awaiting regulatory approval that would forge the largest single group of television stations in America: 42 total.

According to Oliver, the "Last Week" team found out that "when you combine the most-watched nightly newscasts on Sinclair and Tribune stations in some of their largest markets, you get an average total viewership of 2.2 million households… a lot more than any current primetime show on Fox News."

Like Fox News, Sinclair leans heavily to the right. But what's highly unusual about the broadcast group is its production of conservative ads called "must-runs," which it forces its networks to air. They're also a great landing place for Trump surrogates who didn't score a cabinet position or a job with a PAC.

Case in point: "Just recently [Sinclair] hired a man named Boris Epstein a former Trump adviser who you may remember from multiple TV appearances last year, where he made wild [voter fraud] claims" recalled Oliver. "Yet Epstein is now Sinclair's chief political analyst and has a regular segment called 'Bottom line with Boris.'"

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