Democratic Sen. Dianne Feinstein, the longest-serving woman in the Senate, has died. She was 90. She was elected to the Senate in 1992. She became mayor of San Francisco in 1978 after Mayor George Moscone was gunned down beside Supervisor Harvey Milk by a disgruntled former supervisor. Feinstein found Milk’s body.In the Senate, she was one of California’s first two female senators.