Republican congressional candidate Rick Saccone speaks during a rally Saturday in Moon Township, Pa. (Joshua Roberts/Reuters)

PITTSBURGH — The largest newspaper in southwest Pennsylvania endorsed the Republican candidate ahead of Tuesday’s special congressional election with a rationale unlike any cited in other races: Democratic control of the House would hurt the country by setting the stage for a presidential impeachment.

Neither Rick Saccone nor Conor Lamb, the Republican and Democratic nominees in the 18th Congressional District, has talked about impeachment during the campaign. Attack ads from Saccone and allies have portrayed Lamb as a Trojan horse for House Democratic leader Nancy Pelosi, who is deeply unpopular in the district, while Lamb has attacked Saccone for voting for looser gun laws and against funding for opioid addiction treatment. In the House, several liberal members of the Democratic conference have introduced resolutions of impeachment, but just 66 Democrats voted in January to proceed to debate on one of those resolutions.

Rep. Jerrold Nadler (D-N.Y.), who would chair the House Judiciary Committee if his party won a majority, told The Washington Post this year that impeachment would not be pursued unless both parties agreed to it, as removal of the president would require a supermajority vote in the Senate.

Nonetheless, the editorial in Sunday’s Pittsburgh Post-Gazette, which endorsed Saccone over Lamb largely on grounds of experience (Saccone is a longtime state legislator), argued flatly that a Democratic House would drive the country to “distraction” by immediately pushing to impeach Trump.

“If Mr. Lamb, 33, wins, it could well be the start of a Democratic wave,” the editorial read. “The prospect of a Democratic House may please partisans, but it might be bad for the country. The Democrats in the House have only one agenda item at the moment, and it isn’t health care or jobs. It is impeachment. Regardless of whether one likes this president or his policies, one must ask what the consequence for the country will be if we dive into so great a distraction.”

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This was the Post-Gazette’s first endorsement in any race since Keith Burris, the editorial page editor of the Toledo Blade, took over that duty for the Pittsburgh paper. The papers already shared an owner, and they were among relatively few newspapers that did not endorse Hillary Clinton for president in 2016. Instead, the Blade and the Post-Gazette published a 12-point guide to help undecided voters pick between Trump and Clinton, “to cast a protest vote for a third or fourth party, or to abstain altogether.”

Earlier this year, an editorial that ran in both papers attracted national attention for defending the president from accusations of racism after The Washington Post reported that he had referred to some poor, nonwhite countries as “s—hole” countries.

“There are nations that are hellholes in this world,” the editorial read. “And there are failed states. It is not racist to say that this country cannot take only the worst people from the worst places and that we want some of the best people from the best places, many of which are inhabited by people of color. That’s not racism, it is reason.” The Newspaper Guild of Pittsburgh, which represents many Post-Gazette employees, denounced the editorial.

The Observer-Reporter, a smaller newspaper that serves the more rural parts of the 18th district, endorsed Lamb over Saccone late Saturday night.

“In reality, either candidate would probably be able and competent when it comes to representing the 18th Congressional District,” the editorial board wrote. “But we believe one of the two candidates would be better positioned to be the kind of moderate, conciliatory figure that is needed in this tempestuous moment in our political life.”

In 2016, the Observer-Reporter endorsed Hillary Clinton for president; four years earlier, it endorsed Mitt Romney over Barack Obama.