If you've caught many Democratic campaign ads this cycle, you've probably heard of the Koch brothers, the billionaire industrialists who have used their vast wealth to fund conservative causes. Now, labor leaders have found a new pair of Kochs to star in their latest attack spots.

So they're not actually related to the Koch brothers. Or to each other. But they represent the Democrats' latest attempt to turn the Koch brothers into midterm election lightning rods.

In a departure from the ominous attack ads and fiery rhetoric (see Reid, Harry) that have dominated the anti-Koch playbook this year, the AFL-CIO is launching a lighter, more positive campaign featuring the "Koch sisters" -- two women whose last names really are Koch. Their goal: Serve as a friendly counterbalance to the policies the other Kochs have championed.

"We're just two average women who've raised families and worked hard all our lives," says Karen Koch in a 30-second TV ad that launches Thursday. Joyce Koch adds, "We don't have billions to spend on political campaigns."

The ad is running in Kentucky and Michigan, two Senate battlegrounds, as well as on cable nationally. It's the first in what the AFL-CIO says will be a series of ads that will air online and on television. Later commercials will hone in on more specific issues.

The group declined to put a dollar figure on their ad campaign, but spokesman Josh Goldstein called it a "significant" buy. There is also a Web site where visitors can provide their contact information and engage through social media.

The goal of the new campaign, Goldstein said, is to complement the sharply critical tone Reid and other Democrats have adopted with a uplifting message that explains what Democrats stand for and why they oppose the Koch agenda.

The AFL-CIO found both Karen Koch and Joyce Koch by searching a union database for last name Koch. Karen Koch is a member of the Michigan Education Association. Joyce Koch is the wife of a retired American Federation of Teachers educator.

It remains to be seen whether Democrats can successfully turn the Koch brothers into election year bogeymen. A large part of their challenge is that many people don't know much about them. Fifty-two percent of Americans said they didn't know who Charles and David Koch were in a March GWU Battleground poll and 11 percent of respondents had no opinion of them.