There is a reason Martha Coakley went negative. Coakley can win if she rallys her base. There are enough Democrats in Massachusetts for Coakley to win without Republican or Independent support. Still its a bad sign for any candidate, when they are trying to rally their base during the last week of the campaign.
By contrast, Brown's base is fired up. He also has Independents in his corner. Brown is spending his last week in enemy territory. The Boston Globe profiles Brown's foray into Democratic homes, while Brown's latest ad shows him campaigning in Southie, a famous Democratic stronghold:
While Brown fights Coakley on her own turf, his own base cannot let up. His confidence assumes that we will continue to do our part. He doesn't need to rally us. We know the stakes.