Castle "embodied what public service is supposed to look like: thoughtful, principled, and always grounded in doing what was right," Tom Carper says.

WILMINGTON, Del. — Former Delaware Gov. Mike Castle, a Republican moderate who championed creating the popular 50 State Quarters Program of commemorative coins while he served in Congress, has died. He was 86. The Delaware Republican Party announced that Castle died Thursday in Greenville but shared no other details.