Obama is scheduled to answer questions on the video-sharing Web site starting at 2:30 p.m. EST in a live-streamed interview with YouTube news and politics head Steve Grove, formerly an ABC News and Boston Globe reporter.
The session is part of a two-day campaign to talk directly to Americans after the State of the Union speech. Obama spoke and joked with Wisconsin factory workers Wednesday in a visit intended to expand on his State of the Union's "winning the future" theme.
The YouTube questions Obama will answer will be based on the number of votes each question receives, YouTube said.
More than 193,000 people submitted nearly 140,000 questions and cast almost 1.4 million votes by midnight Wednesday, the submission deadline, a United Press International review indicated. This is 10 times last year's 14,000 questions, the first year YouTube hosted an Obama interview.
The top 10 questions all involved ending or changing the government's war on drugs, legalizing or decriminalizing marijuana and embracing industrial hemp as a "green" initiative to help farmers, the UPI review found.
The United States is hemp's biggest importer. China is hemp's leading producer. The U.S. government does not consistently distinguish between psychoactive marijuana and the non-psychoactive cannabis used in industrial hemp.
Along with Obama's interview, U.S. Vice President Joe Biden will answer questions from the public in a Yahoo interview, and four top administration officials will answer questions submitted through the Facebook social-network service. The White House will also sponsor online "policy roundtables" Thursday to discuss the economy, foreign policy, education and healthcare.
The economy roundtable will be hosted by Council of Economic Advisers Chairman Austan Goolsbee, foreign policy by Deputy National Security Adviser Denis McDonough, education by Education Secretary Arne Duncan and healthcare by Health and Human Services Secretary Kathleen Sebelius, the White House said.
The White House's social-media push comes as the Pew Research Center's Internet and American Life Project reported Thursday Obama and other Democrats lost their Internet edge to Republicans, independents and Tea Party movement supporters in the past two years.