The phrase "top staffer" refers to an important employee or person in a higher position within an organization or company. They usually hold a significant role or have important responsibilities. Full definition
A 2010 New York Times examination of top staffers in the gubernatorial election teams of Cuomo and then - opponent Carl Paladino found that «women are suddenly popping up everywhere» in the race — «everywhere, that is, except inside the campaigns» inner circles.» (politico.com)
Headed by Marc Short, a former top staffer in the House and Senate, Freedom Partners dispenses funds and expertise to myriad affiliate groups in the network. (politico.com)