During the 1921 election, Boudreau was defeated by Télesphore St. Arnaud of the United Farmers of Alberta. He returned to office in 1926 (when St. Arnaud did not run), but was defeated again in 1930 by St. Germain, this time running for the UFA. Over the course of the next five years, St. Germain became disillusioned with the UFA, and crossed the floor to the Liberals, meaning that when Boudreau challenged him in the 1935 election, he had to do so as an independent Liberal trying to unseat the Liberal incumbent. He defeated St. Germain on the first ballot (Alberta used a single transferable vote electoral system at the time), but was defeated on the second by Lucien Maynard of the Alberta Social Credit Party. This was the end of Boudreau's political career.