Conversation so far:
who is the head of the dnc now
Thomas Edward Perez has been the Chair of the Democratic National Committee since February 2017.
Who was Tom Perez's predecessor as chair of the Democratic National Committee?
Donna Brazile briefly served as the interim chair of the Democratic National Committee in spring 2011, and again from July 2016 to February 2017.

Question: What does committee do?
Self-contained rewrite: What does the Democratic National Committee do?