Ma likes to joke that her job should really be known as "chief of stuff"—and having now served as a chief of staff in three different institutions over the past decade, she should know. Ma, 44, grew up in Tucson, Ariz., and has a bachelor's degree from the University of Arizona. She stayed out West to serve as the southern Arizona coordinator for the Clinton-Gore campaign in 1996, the first year a Democratic presidential ticket won the state in nearly half a century. In President Clinton's second term, she joined the Labor Department as special assistant to the assistant secretary for employment and training, quickly becoming familiar with such issues as welfare-to-work and unemployment insurance. In 2001, then-Democratic National Committee Chairman Terry McAuliffe asked Ma to be the party's Western political director. She reconnected with her Arizona roots, moving on to serve as senior counsel and chief of staff to Democratic Rep. Raul Grijalva for three terms. In 2009, Small Business Administrator Karen Mills brought Ma aboard to be her chief of staff. Now back at Labor, Ma leads more than 17,000 department employees and is known for her open-door policy and her love of techno-gadgets.