(CBS News) Last weekend, minutes after Mitt Romney officially tapped Paul Ryan as his running mate, the Democratic Senatorial Campaign Committee sent out an email blast. The e-mail, citing a Politico story, touted a recent campaign ad from Montana Senate candidate Denny Rehberg that blasted Ryan's budget plan. What's most interesting about the ad, however, is that Rehberg is a Republican - and that the National Republican Senatorial Committee had helped to fund it.
Democrats across the nation have expressed a certain amount of glee at the prospect of running against Ryan: Unlike Mitt Romney, the seven-term congressman from Wisconsin has a long record with which Democrats can pinpoint his positions on a number of ideological issues.
Congressional Democratic operatives, however, have expressed particular excitement about Ryan's new position: Ryan is the author of a controversial budget plan, which includes an overhaul of the nation's Medicare system so controversial that even some Republicans (see: Denny Rehberg) were running against it.
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"From now until Election Day, Democrats will be on offense and in overdrive, seizing this golden opportunity to define the choice in this election: Republicans putting Millionaires over Medicare and the middle class," said Rep. Steve Israel, chairman of the Democratic Congressional Campaign Committee (DCCC), in a statement. "It's crystal clear that the Ryan budget will be a defining issue in congressional races across the country and House Republicans can't escape the political devastation it will cause them."
Democrats object to a number of elements in the Ryan budget, but the Medicare plan - which would turn Medicare into what's called a "premium support," or voucher, plan - has the potential to be perhaps the most politically potent: Polling has consistently shown that voters tend to be wary of major changes to Medicare and that older voters, particularly, feel strongly about the issue.
According to a Pew poll from 2011 surveying voters on a plan with elements that reflect Ryan's, more voters opposed a voucher-style Medicare system than supported it, a trend which was consistent among Democrats, Republicans, and independents. Older voters were particularly averse to the plan: More than half of people ages 50-65 opposed it, and more than 40 percent opposed it strongly.
Democrats are convinced that educating voters about the Ryan budget and Medicare plan will serve them well in House and Senate races, and are working hard to make them defining issues in those races.
"Montana is not a particularly Democratic-leaning state and the NRSC has got their Republican candidate, who's been in Congress for a long time now, up on television saying, 'I voted against this,'" said one Democratic Senate aide. "I think that tells you how toxic it is even in a state like Montana. Imagine how toxic it is going to be in a state like Virginia, that's more contested."
Senate candidates, the aide said, are working to "make sure they're communicating the impacts of what these policies would do and how they would impact not just current retirees but also future retirees as well."
The idea is to highlight those candidates who voted for the Ryan budget, but even for those who weren't in office at the time and haven't taken a strong position on the issue, "it's kind of hung on their neck regardless," the aide argued. "This is their running mate. This is someone they're tied to regardless."
The DCCC has launched two television ads tying Republicans to Ryan's budget plan, as well as robo-calls highlighting 50 Republican congressional candidates' support for the proposal. Meanwhile, Senate candidates in hotly-contested states - including Elizabeth Warren in Massachusetts, Tim Kaine in Virginia, Claire McCaskill in Missouri, and Shelley Berkley in Nevada - are making Medicare and the Ryan budget prominent issues on the campaign trail.
The DSCC contends that in states like Arizona and Indiana, both of which boast large populations of seniors, the Medicare issue could Democratic give candidates a boost.
"Mitt Romney single-handedly recast the Senate map and improved the landscape for Senate Democrats when he selected Paul Ryan to be his Vice Presidential nominee," said Matt Canter, communications director of the DSCC, in a Friday memo. "While the so-called Ryan plan has already become politically problematic for Republicans across the country, Ryan's selection could prove to be particularly disastrous for Republicans in two key states - Arizona and Indiana."