“President Trump’s quest to unseat Rep. Thomas Massie (R-KY) will come to a head Tuesday, as primary voters weigh whether there is room in the Republican Party for a lawmaker willing to openly defy the president,” The Hill reports.“The race has become the most expensive House primary battle in U.S. history, according to AdImpact, drawing $25.6 million in television, radio and digital advertising, as outside groups and national Republicans flood Kentucky’s 4th Congressional District with bitter attack ads.”