Election Day 2008 will always be remembered for Americans’ voting the first African-American President of the United States into office. But it was also historic for another reason: an estimated 22 million young Americans under the age of 30 showed up at the polls, the third highest turnout rate for young voters in the nation’s history.

Four years later, as Barack Obama addresses the Democratic National Convention in Charlotte, much of that enthusiasm is gone. According to a July Gallup survey, only 58% of registered voters ages 18 to 29 said they will “definitely vote” this fall. That’s well below the 78% of young voters who said the same in the months before the 2008 election. Obama, who won voters under 30 by 34 points in 2008, needs to recapture some of that youthful energy to win his tough re-election battle.

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The President still has an advantage among young voters. A recent poll found that 18-to-29-year-olds prefer Obama to Mitt Romney by a 55%–42% margin. But turnout will be key to making that advantage a significant electoral asset.

In hopes of energizing young voters as he did four years ago, Obama set out on Road to Charlotte, a two-day tour, last Tuesday. The President stopped at college campuses in the battleground states of Iowa, Colorado and Virginia. And his team has been working directly with organizers on college campuses to gear up their efforts for November.

But the Obama campaign isn’t the only organization working to turn out young voters. Groups like Rock the Vote, which kicked off the largest nonpartisan voter-registration campaign in the country on May 2, are trying to re-create the energy of 2008 too.

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With an ambitious goal of registering 1.5 million new voters, Rock the Vote hopes to modernize the election system for a young, technology-savvy generation. “We have an election process that was built for a 19th century voter,” says Heather Smith, the group’s president. Rock the Vote is now able to register voters from computers and mobile devices. It’s partnering with Microsoft’s Xbox and Virgin Atlantic to register people everywhere from their living rooms to 35,000 feet in the air.

There’s even a Facebook app. “The Facebook tool allows us to not just register our friends and our connections, but it allows them to become the organizer, the ambassador,” Smith says. “We used to work in neighborhoods where you knocked on doors. Now we work in networks.” Despite the technological advances, young voters may face obstacles in 2012. Several states have passed controversial laws requiring people to show a photo ID before they vote. Democrats worry that many voters from their traditional constituencies, including the youth bloc, will be turned away at the polls. The Center for Information and Research on Civic Learning and Engagement recently found that 68% of young people don’t know whether their state requires a photo ID to vote. Rock the Vote has planned a September concert in Pennsylvania featuring Hawaii rocker Jack Johnson to educate young people about the laws.

“Our goal is not to tell people what to do but to give them the tools to make up their mind,” Smith says. “Our collective power, if we participate, can change the direction of our country. Young people understand that.” The Obama campaign understands it too.