Crossroads GPS's mission doesn't stop at getting President Obama out of the White House. The Karl Rove-backed conservative organization is ready to unleash a new slew of attack ads directed at Democratic Senate candidates in battleground states. The ad blitz will cost $4.2 million, air Wednesday through next Tuesday, and hit Missouri, Montana, North Dakota, Nevada and Virginia. "Karl Rove is spending millions propping up George Allen, Dean Heller, Denny Rehberg, Rick Berg, John Brunner, Sarah Steelman and Todd Akin because he knows that these Republicans will be a rubber stamp for the special interests that are lining Rove's pockets," said the Democratic Senatorial Campaign Committee's spokesman. "What's worse is that Rove is blatantly thumbing his nose at election laws and allowing billionaires and corporate special interests to avoid federal election law with their anonymous, shadowy donations."