The Democratic Party has an unlikely new friend. His name is Steve Bannon.

You remember Bannon, don’t you? He was the man who is widely credited with being the political Svengali that masterminded the upset victory of Donald Trump.

Bannon told Trump to forget the ways of John McCain and Mitt Romney and go after those Republicans and independents who have been sitting out those general elections and incite them with real red-meat nativist “America first” rhetoric.

Included in the package would be not-too-subtle appeals to bring back the 1950s when the idea of diversity and inclusion was not championed or, for that matter, even mentioned.

Trump took Bannon’s advice and ran a campaign that would make George Wallace proud.

Once in the presidency, Trump has done nothing to unify the country. People or groups that oppose him, he shuns; those more to his liking, he goes after with venal, vicious and vindictive remarks. Trump is more than pleased to have his rock-solid 40 percent cult following.

The 60 percent majority that despise or are totally embarrassed by him, he can just do without.

Sen. Bob Corker (R-Tenn), a very traditional, establishment Republican, has had enough of this president. He speaks for many in his party who have remained silent.

He first said that Secretary of State Rex Tillerson, Defense Secretary Jim Mattis and White House chief of staff John Kelly “are those people that help separate our country from chaos.”

Recently he raised the ante via Twitter: “It’s a shame the White House has become an adult day care center. Someone obviously missed their shift this morning.”

And if that was not enough, Corker warned the country and the world that Trump’s words and behavior are putting the United States “on the path to World War III.”

All this brings us back to Bannon.

After Trump was actually elected, Bannon took up a perch in the White House itself. You might have noticed him prominently sitting in the front row while Trump was behind the podium.

But it wasn’t too long before he fell out of favor. He didn’t get along with Trump’s son-in-law, Jared Kushner, and had a particular disdain for chief economics advisor Gary Cohn.

Bannon was asked to leave.

But instead of being bitter or vengeful toward Trump, he has anointed himself as Trump’s defender-in-chief and protector of his base. Bannon wants to cleanse the Republican Party of elected officials he believes are not of his ilk.

They include Republican senators such as Jeff Flake of Arizona, Roger Wicker of Mississippi and Dean Heller of Nevada. These three are up for re-election next year.

Bannon is actually recruiting candidates to run against these three Republican incumbents.

There are two Democratic incumbents who are up in 2018 and are considered highly vulnerable — Joe Manchin of West Virginia and Joe Donnelly of Indiana.

Heidi Heitkamp of North Dakota falls into the same category.

Trump won West Virginia by a whopping 36 points and Indiana by a huge 18 points. Bannon wants to field not “establishment Republicans” but Republicans who fit his ideological mode. Moderate, non-polarizing electable types need not apply.

Very likely, if Bannon has his way, the Republican incumbents could be defeated in a “Bloody Bannon” primary (Arizona, Mississippi and Nevada). That could produce a contested general where Dems would have a decent chance to pick up three seats.

Couple that with the Dems holding West Virginia and Indiana. Keep in mind both Independents caucus with the Democrats.

Who knows, a political “hail Mary” might arise soon, in which Roy Moore goes down to Democrat Doug Jones in Alabama this December.

There is a scenario by which the machinations of the “Bannon purge” would not result in adding GOP seats, but the absolute opposite would occur.

Democrats pick up a minimum of three seats, possibly four. The Republican Senate becomes a Democratic Senate.

Bannon would be happy, at least: Mitch McConnell (R-Ky.) would no longer be majority leader.

Then, at the first Wednesday lunch of 2018, the new Democratic majority, before diving into its salads, would be instructed to write warm thank-you notes to its benefactor — Steve Bannon.

Mark Plotkin is a contributor to the BBC on American politics and a columnist for The Georgetowner. He previously worked as the political analyst for WAMU-FM, Washington’s NPR affiliate, and for WTOP-FM, Washington’s all-news radio station. He is a winner of the Edward R. Murrow Award for excellence in writing.