Beam on politics: What's working

This gizmo has many allures. You could place, say, 5,000 calls to elderly voters, or to undecided voters, or to registered Democrats voters in Lawrence, and devote the hour-long exchange to their concerns.

The technology features call screening, so the candidate's staff can move on and off topics at will. "The speaker usually tries to diversify the subject matter," explains Shaun Thompson, who works for the vendor Tele-Town Hall in Washington, D.C. "They don't want to answer thirty calls on health care."

There's more. Capuano's people interrupt the calls every 10 minutes or so and conduct mini-polls ("Press one if you think Martha Coakley should just give up" -- kidding!) or solicit volunteers. "That's gravy," says one Capuano staffer. "The main purpose is to bring Mike into people's homes. Everything else is added benefit."

The technology also provides feedback, in real time. The candidate knows how many people are listening, how many are dropping out of the call, and precisely when they are dropping out. It turns out that 15 minutes is about as much political chinwag as the average caller can take.

"It's informative to see when people drop out," reports Jim Spencer, media consultant for the Flaherty-Yoon campaign. "You see maybe the candidate just went on and on about something for too long."

The digital town halls are especially useful for Capuano, who spends much of the week on Capitol Hill. He can speak live to an audience of several thousand people for between $2,000 and $5,000, depending on the volume of solicitations. And it's a lot easier than shaking hands.

II. Do social media sites like Facebook, Twitter, and LinkedIn produce voters? It's hard to separate the idiocy factor (Steve Pagliuca tweets: "New ad folks -- we're really excited about this one.") from effectiveness. Of the four Democratic senatorial wannabes, Alan Khazei's campaign has emphasized social media for obvious reasons. First off, the natural constituency for his storm-the-ramparts populist message is younger voters, and secondly, using social media is a cheap way for an unknown to get a campaign off the ground.

Khazei, a co-founder of the urban service program City Year, announced his candidacy in early September. One of the campaign's first priorities was to seek out sympathizers on Facebook. By canvassing City Year alums, they signed up a thousand Facebook fans in three days. By the end of the month, their online fan base reached about half of Martha Coakley's. Now, wrapping in their Twitter and LinkedIn followers, the Khazei campaign claims more online fans than front-runner Coakley, 11,559 to 10,479.

What are followers worth? "The objective is to move people up the engagement chain," explains Khazei's new media director Jonathan Burckhardt, who worked for both Dean and Obama. Supporters can become volunteers and donors. But will they become voters? "If there were studies on that, I'd be the first to know," Burckhardt says.

We will find out on Dec. 8.

Alex Beam is a Globe columnist. His e-dress is beam@globe.com. Click here to read his previous takes on the campaign trail.