Baldwin ad accuses Thompson of Iran ties

"This is uranium. Iran needs it to build a nuclear bomb. It's now been revealed Tommy Thompson invested in a company that partnered with Iran to mine for uranium, and he invested in another company that's building Iran's nuclear reactor," the ad's narrator says. "And Tommy's D.C. lobbying firm, they worked for a big oil company to weaken sanctions against Iran. Now Tommy Thompson's attacking Tammy Baldwin's patriotism? He's not for you anymore."

The ad is part of an increasingly nasty back-and-forth between the candidates. Thompson released an ad earlier this week slamming Baldwin for voting against a bill honoring the victims of Sept. 11 (she'd voted against the bill because of other provisions), and Baldwin fired back with an ad accusing Thompson of running a health company that was slow to respond to help the attack's victims (others have disputed that).

The two had been largely focused on healthcare issues throughout the campaign — but the last week has been consumed by brutal attacks from each side on the other's patriotism. Polls show a very close race in the state.