Complex sentence: In 1918 he was again elected to the Senate, and in 1921 was a leader of the Republican Reaction Movement, which had the goal of comparing the politics of liberalism against those of the state oligarchies.
Split into simpler sentences: In 1918 he was again elected to the Senate. In 1921 he was a leader of the Republican Reaction Movement which had the goal of comparing the politics of liberalism against those of the state oligarchies.