You may know Glenn Jacobs as Kane, the longtime WWE wrestling star. His constituents in Knox County, Tenn., know him as their next mayor.

But Jacobs also represents something just as remarkable: He is a libertarian-leaning Republican who won an election in a climate dominated by populists on the Right and socialists on the Left. After experiencing some setbacks in federal elections recently, “liberty Republicans” are starting to look down-ballot for success.