Screening at dinner time: A middle-American mom finds her daughter with a bag of weed and some cocaine. Daughter replies: "It's just a little pot, a little blow. It's not like it's smack..."
Running with the surge is not smart for McCain. If Obama's clever (and he is), he would respond that the "surge" merely corrected the disastrous decision by the Republicans not to commit enough troops to Iraq in 2003, a decision Obama could argue cost the lives of thousands of US soldiers over four years. Did McCain argue early on that the US wasn't committing enough troops? If so I don't remember it.
Back on the drugs thing: it doesn't bother me in the slightest, but you'd be surprised how many people, especially parents, it would bother. Portraying John Kerry as a strange, windsurfing elitists worked well at the last election, and a similar line of attack could hurt Obama.