"You're all over the map," President Obama charged in the third debate.

Obama was talking about Mitt Romney, but he could have been referring to those watching, listening, reading, posting or tweeting about the debate and the race, according to a new Pew Research Center study.

"The numbers portray a diverse landscape in which no platform dominates as the place for politics, and the vast majority of Americans say they regularly rely on multiple platforms to get political information. ... The concept of a primary source of news -- a gatekeeper that provides most of what a voter might know -- seems obsolete," according to Pew.

The media mosaic is just one reason why one purveyor didn't emerge as the 2012 campaign's key media source. Another factor was the disconnect between media use and useful media.

For instance, cable news, where 41 percent report they "regularly get campaign news," holds the poll's top spot. But note that Pew was referring to the type of cable news that seeks to emulate Edward R. Murrow -- not cable news talk shows that channel "Network's" Howard Beale, the "mad-as-hell" anchorman. Only 18 percent regularly tune into those programs to follow the race. And the stats were starker when respondents were asked which source is "most helpful" for campaign news -- 24 percent named cable news, while only 2 percent named cable news talk shows.

Hostile hosts can also be heard -- loudly -- on some talk radio shows. But again, respondents found more heat than light: 16 percent cited talk radio as a regular source, but only 2 percent said it was most helpful.

Not to say that talk radio and cable didn't have an influence. But that influence might have been to encourage, or enforce, ideological rigidity instead of letting candidates move to the middle, where most Americans align.

At 38 percent, local news shows were the second-most-used, and 11 percent said they were most helpful. But that's more reflective of a reflexive tune-in, not because of any game-changing content. The same could be said for network news: 31 percent regularly tuned in, and 11 percent called it most helpful. Yet network news didn't have a 2012 media moment quite like Katie Couric's interview of Sarah Palin in 2008.

Despite all the ink about newspapers' challenges, local newspapers were named the top source by 23 percent of Pew's respondents, and national newspapers by 13 percent. But many didn't make it past the jump to being most helpful. Local newspapers were found most helpful by 5 percent, and national papers by 3 percent.

Quadrennial campaigns are eras in media terms. So the remarkable resiliency of TV and newspapers is notable. But so, too, is the ground gained by emergent media forms.

Late-night comedy shows, for instance, were named the top source by 12 percent -- the same percentage as National Public Radio. And while only 1 percent found them most useful, sometimes the satire snuck in a serious side, such as Stephen Colbert's super PAC campaign to highlight the impact of Citizens United.

Since January, the Internet increased dramatically, from 25 percent to 36 percent, as a regular source of campaign news. Mainstream media websites were regularly visited by 28 percent, compared with 19 percent of online-only sources (where a new kind of poll tax -- obsessive observations of the near hourly polls -- hooks many a political and journalism junkie).

Most notably, social media as a regular source doubled from January -- Facebook from 6 to 12 percent, YouTube from 3 to 7 percent, and Twitter from 2 to 4 percent. Yet social media wasn't as useful as usage suggests: Facebook was named by 4 percent, and YouTube and Twitter by 1 percent each, as most useful.

Yet despite soaring social-media numbers, reading the faces of the candidates -- not Facebook itself -- changed the trajectory of the race. The Denver debate was a debacle for Obama and clearly reset the race.

But even that event may be replaced with something more elemental: Superstorm Sandy -- a fittingly dual-gender name in our era of gender gaps and other demographic divisions -- may still impact the race, but it's too early to say how.

Just maybe, the debates and Superstorm Sandy were the most useful events of campaign 2012. Each served as a reminder that even in these technologically transformative times, the most complex media machines are humans.

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John Rash is a Star Tribune editorial writer and columnist.