Comstock worked on behalf of the 2000 presidential campaign of George W. Bush. Her research team built massive stores of paper and electronic data, known as "The Gore File," that were a key source of information on the former vice president for GOP publicists and ad-makers. Comstock is credited with writing the Republican "playbook" defending Bush nominees such as John Ashcroft for U.S. Attorney General. Comstock later served as director of public affairs for the Justice Department from 2002 to 2003.