Complex sentence: In 1916, Norbeck beat Democratic candidate W.T. Rinehart and became the ninth Governor of South Dakota, serving in that office from 1917 to 1921.
Split into simpler sentences: In 1916, Norbeck ran for governor and beat Democratic candidate W.T. Rinehart, becoming the ninth Governor of South Dakota. He served in that office from 1917 to 1921.