WATCH LIVE: @BernieSanders addresses his supporters after winning the Wisconsin primary: on.msnbc.com/1qpGyyr #Decision2016

LIVE: @BernieSanders addresses supporters live from Michigan on.msnbc.com/1RuACtZ #Decision2016

WATCH LIVE: Trump rallies voters in Iowa ahead of today's caucuses: on.msnbc.com/1PQ456v

LIVE: @BernieSanders campaign holds news conference to address DNC data breach claim on.msnbc.com/1lX2yi0

.@POTUS: "This agreement is ambitious, with every nation setting and committing to their own specific targets."

.@POTUS will address nation tonight at 8pmET to discuss terrorism: on.msnbc.com/1jGvOaK (Photo: Getty)

WATCH LIVE: NBC News entering attackers' apartment on.msnbc.com/1NwAnw0

Live coverage of San Bernardino, CA shooting here: on.msnbc.com/1NHWh5G

WATCH LIVE: Chicago mayor Rahm Emanuel and police hold press conference on #LaquanMcDonald case: on.msnbc.com/1PMRUqd

LIVE NOW: Ben Carson answers media's questions after making remarks at Liberty University in Lynchburg, Virginia: on.msnbc.com/1kpA2Vu

WATCH LIVE: Mizzou football coach hosts press conference after school president's resignation: on.msnbc.com/1Sdgtdm

WATCH LIVE: Speaker Ryan leads first GOP leadership press conference on.msnbc.com/1HoQslM

Why the Arctic is so important to the world’s climate: on.msnbc.com/1PMqgcw

WATCH LIVE: Pentagon identifies American soldier killed in ISIS hostage rescue mission: on.msnbc.com/1OWuGvJ

After a short break, the #BenghaziCommittee enters its 9th hour of testimony. Follow along with our live blog here: on.msnbc.com/1hX6hsS

Live blog: @HillaryClinton testifies before House #Benghazi committee on.msnbc.com/1jD0oD1 (Mark Wilson/Getty)

LIVE VIDEO: @HillaryClinton testifies about #Benghazi on Capitol Hill on.msnbc.com/1jD0oD1