A major piece of the legacy Sen. Bob Casey will leave behind when he exits the U.S. Senate next year comes not just from the judges he helped bring onto Pennsylvania's federal bench, but also the way in which he did so.

According to numerous observers, during his 18 years in the Senate, Casey, a Democrat and lawyer since 1988, was diligent about judicial vacancies in a way that helped quickly fill open seats with a speed not all states with split delegations were able to achieve. And, serving the majority of his term with a Republican as his counterpart in the upper chamber, he helped cement a spirit of bipartisanship throughout the process.