WASHINGTON -- Democrats have their thumbs on Republican scales in Senate primaries in Missouri and Wisconsin this summer, hoping to improve their own chances of maintaining a majority in November.
The idea isn't quite as far-fetched as it might sound.
Two years ago, Senate Majority Leader Harry Reid's allies invested heavily in an effort to help Sharron Angle win a contested GOP primary in Nevada after deciding she would be the easiest Republican to defeat in the fall. She won the nomination, but ultimately lost to Reid.
Now Democratic Sen. Claire McCaskill of Missouri is running a series of television advertisements that strategists in both parties say indicates a preference for Rep. Todd Akin over primary rivals John Brunner and Sarah Steelman.
At the same time, Majority PAC, a group with ties to Reid, has run television commercials selectively attacking Republican contenders in Missouri and Wisconsin, where primaries are set for next month.
At first glance, each of the three ads run by McCaskill's campaign appears to be an attack, one at each of her potential rivals.
Yet one calls Akin "too conservative" to be a senator and says he once referred to President Barack Obama as a "complete menace to our civilization" -- characteristics that seem more likely to appeal to Republican primary voters than to repulse them.
In a brief interview in the Capitol, McCaskill said she decided to advertise before the primary because she has been attacked heavily by Republican outside groups and didn't want to wait any longer before telling voters "how extremist, how flawed" the GOP field is.
She sidestepped when asked if she has a preferred opponent, saying they were "three of a kind, one and the same."
Republicans as well as some Democrats said the ad relating to Akin was running more often than the others, and one GOP official, citing detailed advertising information, said it was shown about five times for each airing of the others.
McCaskill's campaign declined to discuss the issue, except to say that all ads are airing statewide.
Democrats now hold a 53-47 majority in the Senate, including the support of two independents. Republicans must gain four seats this fall to be assured of winning control, although a pickup of three would be sufficient if Republican presidential candidate Mitt Romney defeats Obama.
Beginning with a Republican runoff Tuesday in Texas, there are Senate primaries in 15 states through mid-September.
Most of the contested races involve Republicans, although Democrats have a competitive primary in Hawaii on Aug. 11 between Rep. Mazie Hirono and former Rep. Ed Case. The campaign is notable for the cross-party endorsement Hirono recently received from Republican Rep. Don Young of Alaska, a rarity in a hyperpartisan political environment.
Former Gov. Linda Lingle is the Republican in the race.
Missouri and Wisconsin figure to be among the most competitive Senate races this fall, and Republicans have unpredictable multi-candidate primaries in both. McCaskill has trailed in many public polls and has been hit with more than $8 million in attack ads so far by the U.S. Chamber of Commerce and other Republican-aligned groups.
In Wisconsin, surveys suggest Democratic Rep. Tammy Baldwin faces a difficult campaign to win the seat long held by retiring Democratic Sen. Herb Kohl. She, too, has been under attack.
It is fairly common for a candidate of one party to criticize the challenger of another before primaries are held in which there is no doubt about the outcome. But it is relatively rare in other cases, and even rarer that the strategy succeeds.
Two years ago, Reid's allies attacked then-front-runner Sue Lowden in the Nevada Republican primary in an attempt to prevent her from advancing to the general election. "I'm hoping that people see through it," she said not long before she lost to Angle.
While merely emphasizing Akin's conservativism in one ad, McCaskill's campaign seeks to undermine Brunner's credentials in another. It says he has failed to vote in 16 elections since 2000, and cites media reports that he "nearly killed the family business and ran up $245 million in debt. ... Around here, being reliable means showing up to vote, and conservative means you don't spend more than you make."
Steelman is depicted in the third ad as "more politics as usual," and says the former state treasurer was "taking gifts from lobbyists."
A spokesman for Brunner, Todd Abrajano, said, "It's been our contention since these ads were released that Claire McCaskill is trying to pick the winner of the GOP primary." Patrick Tuohey, an aide to Steelman, seconded that, saying that in the ad about Akin, she "picks up a lot of his themes."
Akin said he didn't agree, but acknowledged others might draw that conclusion. "I think she's taking each one of us and saying, `What's my main axis of attack' in the fall," he said.
Strategists in both parties say McCaskill might have an easier race against Akin. They note the congressman has supported earmarks in the past, while the senator has been a prominent foe of them. Polls frequently show conservatives also oppose the practice, in which lawmakers direct federal dollars to pet projects.
Apart from McCaskill's own efforts, a group run by a longtime aide to Reid is airing a commercial that is critical of Brunner, in an evident attempt to cut into his support in the primary and potentially in the fall campaign as well. It says that while he pledges to cut the government debt, he "saddled his own company with nearly $195 million in debt ... and under Brunner's leadership the company nearly shut down."
The same group, Majority PAC, recently launched a television commercial in Wisconsin criticizing two of four Republican primary contenders. It says former Gov. Tommy Thompson worked at a "D.C. lobbying firm that represents pharmaceutical and insurance firms," and attacked Eric Hovde as a "D.C. fund manager who's invested in bailed out banks involved in fraudulent loans."
The ad makes no mention of former Rep. Mark Neumann, who runs third in the preprimary polls, and whom Democrats say privately could be an easier-to-beat challenger.