Sen. John Kerry (D-Mass.) underwent a successful hip replacement surgery Monday at Massachusetts General Hospital and is expected to be released within days. Kerry, 66, had his left hip replaced during the scheduled procedure. He underwent a similar operation in August on his right hip, which temporarily required him to walk with the assistance of a cane. An aide said Kerry purposely scheduled the procedure over Congress’ winter break and expects to be healthy enough to return to work when the Senate resumes Jan. 19.