Before completing his studies, Winans was drawn by news of the California Gold Rush, and in March 1850 left for California by an overland route to seek his fortune. Arriving July 20, he engaged in mining first on the north branch of the American River near Placerville. He continued the same work with some varied success in different parts of the state. In 1853, he was one of the members of the celebrated Randolph Hill Mining Company in the town of Rough and Ready (now a town west of Grass Valley in Nevada County).
Winans entered politics in 1861, serving as a member of the Michigan House of Representatives, a position he held until 1865. Winans won election to the Michigan governorship in 1890, and was sworn into office on January 1, 1891.