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As the final weekend of campaign 2012 approaches, voters in battleground states can’t escape the last-minute messaging from both campaigns. But as the airways are saturated with ads, candidates have increasingly turned to yet another weapon to get their message out: the digital billboard.  

Mitt Romney’s campaign has used digital billboards in states like Florida and Colorado, typically to coincide with Obama campaign rallies. When the president visited Orlando in early August, Romney welcomed him courtesy of a digital billboard featuring Lou Ramos, owner of the Tampa-based business Value Enterprise Solutions, Inc., and the then-popular line on the stump, “Mr. President, I built my business.”   

Romney employed the tactic again outside a Sloan’s Lake Park rally in Denver with a digital billboard featuring a frowning POTUS and the line, “If you've got a business, you didn't build that. Really?"  

That billboard was spotted and highlighted in a pool report by Mark Landler of The New York Times, as the president’s motorcade made its way out of Denver.

The Obama campaign hasn’t employed any large roadside digital billboards, but it did launch a digital advertising campaign throughout the DC Metro system to target voters in Northern Virginia.

Down-ballot campaigns have adopted the tactic as well. Heather Wilson’s (R) Senate campaign in New Mexico used digital billboard technology to attack Rep. Martin Heinrich (D-N.M.) on the deficit. The billboard displayed a running national debt counter above the words “We can’t afford Heinrich.”

The increased use of the billboards is thanks in part to an effort by the outdoor advertising industry, which has worked to sell campaigns on the tactic. The pitch, says Ken Klein, executive VP of government relations with the Outdoor Advertising Association of America, is that they offer a level of speed and flexibility that TV and radio can’t.

Once you have a digital billboard operational, the message can literally be changed in minutes and can feature plenty of variation. Klein says the prep time on Romney’s digital billboard ads in Orlando was just two days, and they managed to generate plenty of local media buzz.

Digital billboards are not without their share of controversy however. Citing safety concerns, a number of locales have enacted temporary bans on the billboards and others are working towards that. Still, the tool has been alive and well on the trail for the past few months, with more than a dozen candidates and a number of outside groups employing the tactic.       

“The digital billboard industry has really been pushing hard, saying they’re effective because they change every minute,” says Mary Tracy, president of Scenic America. “I don’t know who’s seeing these things, but it can really come back to bite a politician, who is saying we should reduce energy consumption, because [the billboards are] bad for public safety. They’re a visual distraction to drivers and energy guzzlers.”

But even Tracy admits the billboards are growing in number. The city of Reno, Nev. passed a voter referendum to prevent the construction of new billboards, hoping the old ones would fall into disrepair, but now there’s a move to convert existing billboards to digital.

“The industry has been generous to politicians,” says Tracy. “You certainly see them wandering around the halls in Washington.”

Tracy says her group works with local officials to deter the use of digital billboards, but hasn’t actively discourage candidates from using the billboards as advertising vehicles—at least not yet.

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