Just ask Karl Rove.
“McCain has gone in his ads one step too far, and sort of attributing to Obama things that are, you know, beyond the 100-percent-truth test,” said Rove. “Both campaigns ought to be careful about… there ought to be an adult who says: ‘Do we really need to go that far in this ad? Don’t we make our point and get broader acceptance and deny the opposition an opportunity to attack us if we don’t include that one little last tweak in the ad?'”