The DFL's endorsed US Senate candidate - Jerry Janezich - has finally joined his major primary opponents in running ads. Janezich is starting with radio ads, weeks after three of his opponents began television advertising. One of them - Michael Ciresi - first started running T-V ads in February, and began another big television ad buy this week. In the latest in our series of Ad Watches, Minnesota Public Radio's Laura McCallum asks analyst Dean Alger to review the Janezich and Ciresi ads....