Washington -- The good news for Democrats is that the 15 seats they need to win a majority in the House of Representatives is, by historical standards, well within reach. In the 10 elections that fell in the sixth year of an administration over the past century, the president's party lost an average of 30 seats, double what Democrats need to elect House Democratic leader Nancy Pelosi of San Francisco as the first female speaker of the House. The bad news for Democrats is that just a small fraction of the 435 House seats -- as few as 1 in...