At a rally here in Arlington last weekend, Speaker Mike Johnson took a selfie video of himself and roughly 500 people cheering and sent it to Donald Trump. At a campaign event about 500 miles south in Harlingen, the speaker whipped out his famous Trump impression. And before the former president hosted a rally in Butler, Pennsylvania — returning to the scene of the July assassination attempt — Johnson tried to call him on the phone with a group of Republican lawmakers for moral support....