His business career was in real estate, but he was always interested in politics and worked on several campaigns.
He made an unsuccessful bid for President of the St. Louis Board of Aldermen in 1943, losing to Aloys P. Kaufmann.
Darst was a proponent of urban renewal through slum clearance and the construction of large scale affordable public housing.
He successfully lobbied the Missouri Legislature to pass legislation enabling the earnings tax.
He died just two months after his term of office expired at age 64, and was buried in Calvary Cemetery.