Original sentence: The "Rockefeller Republican" label is sometimes applied to such modern-day politicians as Senators Olympia Snowe and Susan Collins of Maine, all representing Northeastern states
Edited sentence: The "Rockefeller Republican" label is sometimes applied to such modern-day politicians as Senators Olympia Snowe and Susan Collins of Maine.The 2009 departure of Pennsylvania senator Arlen Specter from the Republican party further reduced their numbers