Team Logo. The Harrisburg Senators are a team in the Eastern League. They are the Double-A affiliate of the Washington Nationals. They get their nickname because Harrisburg is the capital city of Pennsylvania. Retrieved from "https://prosportsteams.fandom.com/wiki/Harrisburg_Senators?oldid=6228" Categories: Eastern League teams Teams in Pennsylvania Add category Cancel Save Community content is available under CC-BY-SA unless otherwise noted.