Watch: Katie Couric's interview with Bernie Sanders.

This afternoon at 3 p.m. EDT, Yahoo global news anchor Katie Couric will interview presidential hopeful Senator Bernie Sanders about his bid for the White House, whether he can realistically defeat Hillary Clinton, the midnight expiration of controversial provisions of the Patriot Act and why he may be voting for the USA Freedom Act, which would allow some counterterrorism tools — including the NSA’s controversial bulk data collection — to continue.

The longest-serving independent in U.S. congressional history, the Vermont senator, who calls himself a socialist, entered the race to win the Democratic nomination on April 30. Last week, in a more formal campaign launch against the backdrop of Lake Champlain in Burlington, Vt., Sanders promised to “fight to protect working families” and warned the nation’s billionaires that they “can’t have it all.”

To watch Katie’s interview with Sen. Sanders, click here at 3 p.m. EDT.