"Never before in an election cycle has so much attention turned to the youth vote, and Luke will bring a unique perspective to covering it," NBC News president Steve Capus said in a statement.
A recent graduate of Boston College with a double major in history and communications, Russert was the picture of poise when he appeared on Today and CNN's Larry King Live in the days after his father's sudden death.
He has co-hosted a sports-radio talk show -- XM Satellite Radio's 60/20 Sports -- with political pundit James Carville for the past two years.
"I am extremely humbled and grateful that NBC News is giving me this opportunity," Luke Russert said in a statement. "I believe youth issues will continue to play a significant role during this election and I want to do my part to report them honestly and objectively."
Brian Williams will lead convention coverage on NBC News.
Williams will anchor Nightly News from Denver and St. Paul on convention nights and will also anchor one hour of primetime coverage each night from 10 p.m.-11 p.m. -- the keystone in more than 200 hours of convention coverage on NBC, MSNBC and CNBC.
Meet the Press will also originate from the convention sites. Tom Brokaw will helm the Sunday-morning program from Denver Aug. 24 and from St. Paul Aug. 31.
Today's Matt Lauer and Meredith Vieira will split convention duty. Lauer will co-anchor Today from Denver Aug. 28 and 29, while Vieira co-anchors from New York. Vieira will travel to St. Paul to co-anchor Sept. 4 and 5 with Lauer back in New York.
MSNBC will be practically wall-to-wall for both conventions with 20 hours per day of live programming beginning at 6 a.m. with Morning Joe live from both sites. Keith Olbermann and Chris Matthews will co-anchor MSNBC's primetime convention coverage from 7 p.m.-2 a.m. each night.
Matthews' Hardball and David Gregory's Race for the White House will also originate from Denver and St. Paul. Gregory will also report live from the convention floor in Denver and St. Paul for both MSNBC and NBC News.
CNBC chief Washington correspondent John Harwood will be at both conventions to provide economic analysis for the network.
Telemundo's Pedro Sevcec, who hosts the Spanish-language channel's Noticiero Telemundo, will report live from the conventions on all four nights. Washington correspondent Lori Montenegro will cover the Democratic convention, with Los Angeles-based correspondent Carlos Botifol at the Republican convention.