Former Sen. Tom Coburn, the Oklahoma Republican who enraged his own party's leadership with a jihad against bipartisan pork during his time in the House and Senate, earned the nickname "Dr. No." But Coburn just said yes.

He has endorsed Judge Roy Moore in Alabama's Senate runoff, lending the current frontrunner even more anti-establishment credibility.

"Men with a backbone of steel are hard to find these days, and even harder to find in the U.S. Senate," Coburn wrote in a statement. "I proudly endorse Judge Moore because we need him to be a conservative voice in the Senate. He is a man who can't be bought, who won't fall in line with the Washington establishment and who will stand up for what he believes in."

That race quickly became a proxy war as soon as Majority Leader Mitch McConnell, R-Ky., threw his weight behind incumbent Sen. Luther Strange. A dissatisfied populist base rallied first to Rep. Mo Brooks, R-Ala., before backing Moore. Strange secured second place in that race, forcing the Sept. 26 runoff with the endorsement of President Trump.

Since then, Moore has been endorsed by everyone from Chuck Norris to Freedom Caucus Chairman Mark Meadows, R-N.C. The Coburn nod further solidifies that outsider brand.

Philip Wegmann is a commentary writer for the Washington Examiner.