With little fanfare or media coverage, the Obama campaign is promoting a new method of voter registration for Nevada residents while it wrestles with a drop in registration among the swing state's young adults. A page on the Obama for America website explains how Nevadans can register merely using an app on a smartphone, iPad, or similar device: "When you sign using your touch screen, you'll be controlling the movements of an actual pen that will place your signature on your printed voter registration form for you." In other words, a mechanical pen at another location copies your digital signature.

Scott Gilles, the Deputy Secretary of Elections in Nevada, said the technology is legally acceptable there. "The system that's being implemented is going to result in our county clerks receiving a voter registration form with a wet signature on it," he told the blog TechPresident. "They're not going to be able to verify how that signature was produced."

Verafirma, a California-based company, is promoting the technology, owned by a little-known startup called Allpoint Voter Services. Verafirma pioneered another mobile voter registration system in California in 2010, which submitted to state voting officials encrypted digital signatures that residents had written onto iPhones. (The company also used its technology to collect digital signatures for petitions to legalize gay marriage and marijuana in the state.)

A new study from the Pew Center on the States estimates one in four eligible Americans is not registered to vote. Voters between the ages of 18 and 24 were important to President Obama's victory in 2008: Although young adults comprised 11 percent of Nevada's registered voters four years ago, the proportion had declined to an unenthusiastic 8 percent last October.