Posted Wednesday, September 26, 2012 --- 1:45 p.m.

MADISON, Wis. (AP) -- Karl Rove's political action committee Crossroads GPS is pouring another $1.2 million into ads attacking Democrat Tammy Baldwin in Wisconsin's U.S. Senate race.

The group unveiled its latest attack ad on Wednesday calling Baldwin "too extreme for Wisconsin." She is running against Republican Tommy Thompson.

The spending by Rove's group comes on top of $961,000 it spent last week. It had previously spent $500,000 on anti-Baldwin ads.

Also on Wednesday, Gov. Scott Walker and former U.S. Rep. Mark Neumann sent fundraising pleas on behalf of Thompson via email.

The flurry of spending comes after polls last week showed the race a dead heat, or Baldwin ahead, and Thompson admitted his campaign was broke after the mid-August primary.

Copyright 2012. The Associated Press.