I think what ha scared Coleman was last week’s Minnesota Poll that showed him trailing Franken by 9 points.
Many of those polled said that they were turned off by Coleman’s negative attcks on Franken.
There are many who consider the polling methodology to be flawed and this poll to be an outlier.
But either this poll has spooked Coleman into shutting off the negative ads or his own internal polling is showing that the negative ads are hurting him.
Hard to say which one is which...