Back in 1994, I wrote a column for U.S. News arguing that Republicans had a serious chance to capture a majority of seats in the House of Representatives. The article appeared on the newsstands on July 11, and was the first article I’m aware of that suggested that Democrats might lose the majority they had held for 40 years. My argument was based on a number of polls showing Democratic incumbents trailing Republican challengers. Usually House incumbents don’t trail challengers in polls at any point in the campaign, because they almost always start off better known. For an incumbent to...