Complex sentence: Hayward was elected as a Republican to the United States Senate March 8,1899, to fill the vacancy in the term beginning March 4,1899, caused by the failure of the Nebraska Legislature to elect a Senator by the start of the term.
Split into simpler sentences: Hayward was elected as a Republican to the United States Senate March 8,1899, to fill the vacancy in the term beginning March 4,1899. This delay was caused by the failure of the Nebraska Legislature to elect a Senator by the start of the term.