Secretary of State John Kerry and other administration officials escalated their campaign to win support for the Iran nuclear deal, traveling to the Capitol for a pair of closed-door briefings.

"This is a day we've been looking forward to," Kerry said Wednesday, as he made his way into the first of the briefings for House and then Senate lawmakers. "We get to get out of the politics and into the facts."

Kerry was joined by Energy Secretary Ernest Moniz and Treasury Secretary Jacob J. Lew. All three are scheduled to testify in an open hearing on Thursday before the Senate Foreign Relations Committee.