
Congressional investigators are demanding Ukraine-related documents from the White House, Vice President Mike Pence, and the State Department. So far, they've had little success.
(Image credit: Thanassis Stavrakis/AP)

Congressional investigators are demanding Ukraine-related documents from the White House, Vice President Mike Pence, and the State Department. So far, they've had little success.
(Image credit: Thanassis Stavrakis/AP)