Much better than those sugar sweet “I’m You” ads
Pace and timing. The first step was to introduce herself to the "mushy middle" and reassure them that she's not what the media is painting her to be. Basically, get the "I'm not crazy" idea out there (q.v. Angle in Nevada).
Now, she's hitting Coons with attack ads, and hitting him hard. Her best chance is, now that she's downplayed the "kook" card, to make the election about Coons and Obama.
10 days to go, and a lot of material to use. I wouldn't be surprised to see a new hammer drop every other day -- just enough time to let the previous one play out.