WASHINGTON -- Three days before the Nov. 2 election, Oregon Rep. David Wu’s most loyal and senior staffers were so alarmed by his erratic behavior that they demanded he enter a hospital for psychiatric treatment. Their concern had been spiking for weeks in tandem with Wu’s increasingly unpredictable performance on the campaign trail and in private. He was loud and sometimes angry, some of them told The Oregonian. He said kooky things to staff and -- more worrisome with a tough election fast approaching -- around potential voters and donors. Most of all, they were worried for Wu, a 55-year-old...