Crossroads launches $4.2 million Senate offense focused on Dem-leaning races

The Montana ad has $308,000 behind it, a significant buy for the small state, while the group is spending $164,000 in New Mexico.

The Florida ad attacks Sen. Bill Nelson (D-Fla.) for backing Democrats' health insurance overhaul bill, saying it hurts Medicare.

"Florida's seniors are facing a healthcare crisis — only 14 physicians to every 1,000 Medicare beneficiaries," says the ad's narrator. "But in Washington, Bill Nelson's been voting for the new healthcare law which cuts Medicare spending by $700 billion, puts unelected bureaucrats between Florida's 3 million Medicare recipients and the care they need, hurting Florida seniors. Tell Senator Nelson: It's time for repeal."

The other ads hit Rep. Martin Heinrich (D-N.M.) for voting for "big Washington spending" in stimulus by pointing out some of the more odd things the law funded ("almost $2 million to California to collect ants, almost $300 million to Texas to study weather on Venus"), blame Sen. Jon Tester (D-Mont.) for the federal deficit increasing by $3.5 billion a day, and blast Sen. Sherrod Brown (D-Ohio) for backing the stimulus and healthcare law.

The Democratic Senatorial Campaign Committee fired back.

"Karl Rove is spending millions propping up Denny Rehberg, Josh Mandel, Connie Mack, and Heather Wilson because he knows that these Republicans will be rubber stamps for his agenda that puts Wall Street, Big Oil, and millionaires ahead of seniors, small businesses, and the middle class," said DSCC spokesman Shripal Shah. "As voters learn more about these dangerous, anti-middle class policies, they'll quickly realize that they can't afford to send Republicans who support this agenda to the Senate."

—This post was updated at 11:12 a.m.