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When President Obama takes the stage at tonight's Democratic National Convention in Charlotte, N.C., he'll make a pitch for why he deserves a second term and why the youth voters he so energized in 2008 should stay in his corner this time around.

But miles away on the West Coast, there's another primetime show tonight - one starring Rihanna, Taylor Swift, Green Day and P!nk - that threatens to steer youth attention away from the convention and toward rows of silver Moonman statues. MTV's Video Music Awards kick off at 8 p.m. ET.

It is one of the network's most plugged-in events. Last year, the Los Angeles-based awards show drew 12.4 million total viewers, setting an all-time record.

The award show runs for two hours, so it will overlap with much of the convention's final night in Charlotte, N.C. This year, though, MTV executives decided to move the show up an hour from its normal 9 p.m.-to-11 p.m. time slot so it would end before Obama's 10 p.m. nomination acceptance speech.

"We knew that the DNC was taking place [this] week, so we planned on airing the show during an earlier time-frame," an MTV spokesperson told ABC News. "The VMAs mark one of the biggest nights of the year for MTV, and it's critical that we use the show as a platform to encourage youth voter participation."

MTV News and the "Power of 12? campaign have teamed up to cover both the Republican and Democratic conventions, and the network live-streamed Gov. Mitt Romney's Republican acceptance speech last week on MTV.com, MTVNews.com and Powerof12.org. It will, likewise, live stream Obama's acceptance speech online tonight starting at 9:45.

Throughout the show, MTV will encourage young people to register and vote, but it will not plug Obama's live stream speech, according to network officials.

The VMAs are being hosted by comedian Kevin Hart and will feature awards presentations by actress Rashida Jones, singer Ke$ha and U.S. Olympic gymnasts Alexandra Raisman, Gabby Douglas, McKayla Maroney and Kyla Ross, among others.