It's happening in several congressional races, in states like Nebraska, Montana and Ohio — millions of dollars from out-of-state donors and outside groups are fueling candidates' war chests.
Last week in Indiana, outside money helped Richard Mourdock beat out six-term incumbent Sen. Dick Lugar in the GOP primary.
On Wednesday, WCPN's David C. Barnett reports for NPR's Morning Edition about the congressional race in Ohio's 9th District. The Republican challenger there is Joe Wurzelbacher, aka "Joe the Plumber," the guy who rose to fame in 2008 by tangling with then-candidate Barack Obama. The incumbent Democrat is Marcy Kaptur, and $3 out of every $4 in the race has come from donors who don't live in Ohio's 9th.
When did so many Americans decide races outside their backyards were important enough to back financially?
NPR's science correspondent, Shankar Vedantam stopped by Morning Edition with recent social science research that could provide some answers.
"Across the United States, money is pouring into congressional races that comes from outside the congressional district, and there's another thing that's happening at the same time, which is a lot of the money is increasingly coming from donors who identify themselves as strongly partisan," Vedantam explains.
He points to an article in the latest issue of American Politics Research by Ray La Raja and David Wiltse.
In 1972, 40 percent of donors to congressional and presidential races identified themselves as liberals or conservatives. Today, the number is about 60 percent, says La Raja, a political science professor at the University of Massachusetts, Amherst. Along with that partisan spike comes a similar trend in political contributions: Donors are using their money to weigh in on ideological national issues, such as abortion, gay marriage and foreign policy, instead of focusing solely on local issues.
"What La Raja's research seems to suggest is that Washington's polarization came first, and starting in about 2002, there has been this really growing polarization among the voters, which is translating into more partisan donors in politics," Vedantam says.
And, why is 2002 so important to La Raja's findings? He says that's when political campaigns really began to focus on online fundraising.
"Now, you're sitting in front of your computer, you get an email that says, 'Look what those people are doing to us in Washington.' You have your credit card ready — the people who are motivated by that are passionate about the issues, they're ideological. They send money," La Raja says.
Campaign fundraising has become a "self-reinforcing system," Vedantam says, where politicians appeal to those partisan contributors who are likely to give money to a particular cause or campaign, and the cycle encourages itself again and again over each political year.
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