CORRECTION -- The original version of this feature misstated how the consulting firm of Chong and Koster has been involved with Google's geographically-targeted advertising product. The firm has tested Google advertising products before they were launched publicly to political and non-political clients. The script below has been corrected.

TEXT OF STORY

Kai Ryssdal: The good people at Gallup released their latest political poll results this week. The president basically breaks even, he's right around a 50 percent approval rating. Congress does somewhat worse. Only 16 percent of Americans say they approve of how lawmakers are doing their jobs. So with an election coming up this fall, it is no wonder that one estimate from the Center for Responsive Politics says politicians are going to spend almost $4 billion either holding onto their jobs or getting elected for the first time this fall. There is, of course, a whole industry dedicated to getting a slice of that pie.

And as Brett Neely reports now from Washington, there's a new kid on the block, a very big new kid.

BRETT NEELY: During the recent special Senate election in Massachusetts, ads like these flooded the airwaves.

AD: My name is Scott Brown, and I'm running for the United States Senate. This is my truck.

Aside from pitching his truck, Republican Scott Brown also pitched voters with an aggressive online campaign.

When voters googled Martha Coakley, Brown's opponent, they saw plugs for Brown in the list of sponsored links on the right.

Rob Willington is Brown's online strategist. He says with Google's help the campaign was able to precisely target key markets.

ROB WILLINGTON: So if you lived within a 30 to 45 mile radius of one of our offices, you were going to see ads saying volunteer this weekend for Scott Brown, all over the place in the top 200 Web sites in Massachusetts.

Welcome to the world of Google-powered elections. The company calls that tactic a network blast. In Massachusetts, Willington says those blasts cost about $25,000 a day. Far less than TV and worth every penny.

WILLINGTON: People think Google is a search engine, that's just one part of it. It's the new TV. It's not a niche media market anymore, it is mass media.

Most political campaigns spend at most 3 to 4 percent of their budget on online ads. The Brown campaign spent almost 10 percent -- about $250,000. It's the biggest success so far in Google's campaign to rule the online political advertising business. In 2007, the company started a small team to help politicians tweak their messages online.

PETER GREENBERGER: We can provide advice on which Web sites within our network to target, how to create your video.

Peter Greenberger runs Google's political advertising unit. Even though most campaigns still spend relatively little on online ads, Greenberger says Google's political ad business is profitable, and it's got a bright future.

GREENBERGER: There are over a half-a-million elected officials in the United States. We think that every single elected official could benefit from using Google AdWords to communicate with their voters.

Meredith McGehee of the Campaign Legal Center says the economy also has something to do with why Google has gotten into the business.

MEREDITH MCGEHEE: Google wants to play a role because politics to some degree is recession-proof.

She says the Supreme Court's recent decision to lift restrictions on corporate political spending will probably also help Google. But she's also worried about abuse.

MCGEHEE: The online advertising is generally kind of a Wild West. It's not clear exactly that you have the same kind of rules in terms of disclosure.

TV and radio stations have to keep a public file of political ad clients. Google doesn't. And Google says that they don't track their clients because the ad services they provide are largely do-it-yourself.

Already, a new generation of campaign consultants are spreading Google's gospel to candidates.

Josh Koster is a partner with the liberal political consulting firm Chong and Koster.

JOSH KOSTER: Google was the very first place we ever bought an ad, and the place we spend most of our budget to this day.

Koster's firm has used several new Google advertising products. Some, such as geographical targeting, have also been picked up by movie studios and car companies and later used in targeted corporate marketing efforts.

Koster says that's the real reason Google has gotten into politics.

KOSTER: And ultimately I think that what they learn in politics, and the case studies they get in politics, they can turn around and help sell any industry.

He says if a campaign can win an election with smart, cheap advertising using Google, imagine what a small business can do.

In Washington, I'm Brett Neely for Marketplace.