Good point:

A Republican strategist privy to much of the polling conducted in House districts said that, at this point, it is not difficult to count enough vulnerable districts to show how Democrats can take control. But he offered a cautionary point: "I don't know of a single target race," he said, where the Republican candidate "has spent more than 20 percent of what they intend to spend. The battle is just beginning. That's what people really forget."