The White House came close this week to facing yet another crisis, this time over a railroad dispute that could have taken a crowbar to the U.S. economy ahead of crucial midterm elections. But in the end, a tentative deal was struck, with both sides crediting the Biden administration with stepping in to help avert a strike that was set to begin on Friday — one that could have further disrupted the nation’s fragile supply chain. Administration officials became involved in the talks weeks ago, lobbying both sides around the clock to argue the stakes were too high for a...