Answer
Mussolini served in the Italian Senate during the 26th legislature from 2013 to 2014, representing the Lazio constituency. He was elected as a member of the centre-left Democratic Party. During his time in the Senate, he served on the Committee on Foreign Affairs and Emigration. However, it's important to note that Benito Mussolini, the fascist dictator of Italy, never served in the Italian Senate.