The Democratic Senatorial Campaign Committee today launched its second TV ad in Montana, where Sen. Jon Tester (D) is fending off a challenge from Rep. Denny Rehberg (R) in what is expected to be one of the closest races in the country.

The ad is similar to the one the DSCC began running on Aug. 7, as it criticizes Rehberg’s votes in favor of pay raises for Members of Congress and labels him a “millionaire” and “one of Congress’ wealthiest Members” in the opening seconds.

“Dennis Rehberg — out for himself, not us,” the ad’s announcer says.

https://www.youtube.com/watch?v=S5wpL9U8Yyw

The strategy of the spot is to undercut Rehberg’s ability to form a connection with potential swing voters. Both ads were part of a $3.2 million reservation the DSCC’s independent expenditure arm placed in May.

The negative ads are airing just as Tester begins running a positive spot highlighting several votes that the campaign hopes will show he’s independent of his party. Rehberg has used the same strategy in his own TV ads.

Rehberg has benefited from outside spending as well, and that could increase as the National Republican Senatorial Committee and other GOP-aligned outside groups have said they will not spend in Missouri on behalf of Rep. Todd Akin (R), whose comments about rape and pregnancy have been roundly denounced. Winning the Big Sky State was always crucial to the GOP’s efforts to win a Senate majority, but the stakes are even higher today with Missouri a question mark for national Republicans.