In 1990, a bikini-clad Madonna wrapped in a U.S. flag urged MTV viewers to vote in Senate elections as the youth television network partnered with a "Rock the Vote" campaign that mixed pop culture and politics.

Thirty years on, with Millennials and Gen Z poised to outnumber the Baby Boomer generation for the first time in a U.S. presidential election, MTV on Tuesday launched its most ambitious turnout campaign ever, reaching beyond celebrities to tap into burgeoning youth activism.

The year-long "+1thevote"  initiative across MTV's multiple TV platforms, social media and live events includes plans to open new polling stations at college campuses, sponsor school proms that host registration drives, and integrate voting messages into shows.

"You need to look no further than the climate change strikes and what is happening in the streets to see that this is a fired-up generation," said Brianna Cayo Cotter, SVP of social impact for MTV and its affiliate platforms VH1, CMT and Logo.

"But they have to vote in this election to take that passion and turn it into political power. That's the aim of this campaign - how do we help young people, who are so passionate but for whom voting today was not really designed," she told Reuters.

The campaign is aimed at first time voters, especially the 4 million Americans who will turn 18 in time for the Nov. 8 presidential elections. It aims to make voting an experience to be shared with friends, or a "plus one."

Millennials and Gen Z - those born between 1981-96 and after 1996, respectively - will make up 37 percent of the U.S. electorate, according to a January report from the Pew Research Center, outnumbering for the first time Boomers born between 1946-64.

MTV, a unit of Viacom, is well-placed to catch their attention as the most-watched non-sports U.S. cable network in primetime with 18-34 year olds, according to Nielsen data.

The past three years have seen a boom in youth activism on issues ranging from climate change, partly inspired by 16 year-old Swedish activist Greta Thunberg, to gun control, civil rights and immigration.

Yet for the two generations raised on the internet and smart phones, the process of registering and voting can seem bewildering, MTV found during months of research.

"People have questions that are like, 'What do I wear to vote?', and 'Where do I go?' To young people who can order anything on their phones automatically, the fact that in a lot of places they would have to go to a post office and get a stamp feels crazy," said Cayo Cotter.

Part of the +1thevote campaign involves a partnership with Campus Vote Project and two other grassroots groups to create dozens of new polling stations on college campuses and in local communities nationwide to make youth voting more accessible.

Some 1,200 polling stations have been shut down across the Southern United States since 2014, according to a September report by the Leadership Conference on Civil and Human Rights.

The MTV initiative also includes a drive to integrate voting messages in TV shows across the industry and plans to register voters waiting in line at MTV events like the Video Music Awards.

"If we can use our platforms' superpowers to reach an untapped and largely ignored audience, we're going to be able to unlock an incredible amount of first time voters that otherwise would probably sit this election out," said Cayo Cotter.

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