Complex sentence: The national political upheaval that ushered in the New Deal era in the 1930s benefited the Ohio Democratic Party and party politics in Ohio became very competitive, with Republicans and Democrats trading victories at all levels.
Split into simpler sentences: The national political upheaval that ushered in the New Deal era in the 1930s benefited the Ohio Democratic Party. Party politics in Ohio became very competitive, with Republicans and Democrats trading victories at all levels.