Full retreat: Why is the DCCC spending heavily in Democratic areas?

One of my guys looks at this chart and a few other DCCC buys, along with a rumor that the committee is reserving $2 million in advertising space in the Boston market for either New Hampshire seat or the open-seat race in Massachusetts’s 10th district, and concludes, “By my count, $12 million of the $48 million the Democrats have indicated they’re using to reserve ad space is in the media markets of Philadephia, New York state, California, Boston, and Chicago . . . This buy is recognition that they are in full retreat.”