Monje served as deputy policy director at Obama for America and a special assistant in President Obama’s DC Senate office where he handled homeland security and veterans affairs. He was helpful with the Senate confirmation of two cabinet secretaries as part of the Obama transition team’s 2008 national security working group. Monje was chief of staff of the United States Domestic Policy Council and Special Assistant to the President during the Obama administration. He previously served as Acting Under Secretary and he was nominated by President Barack Obama in 2014 and 2015 to be the Assistant Secretary for Transportation Policy for the U.S. Department of Transportation, he was confirmed by the Senate on March 16, 2015 by a vote of 94–0. He then oversaw implementation of surface transportation programs, the discretionary grant programs, and efforts to promote equity and economic development.