Donald Trump is the undisputed king of the Republican Party. Earlier this month, Trump exacted revenge on Indiana state senators who had opposed his call to redistrict the Hoosier State; his endorsees won a majority of races against incumbents. Then Trump successfully nuked Sen. Bill Cassidy (R-La.) from political life, relegating the incumbent to a shocking third place in his statewide primary. And the next Tuesday, Trump-endorsed candidates across the nation won every primary race — 37 victories and zero defeats. Overall, Trump’s approval rating among members of his own party sits around…