Marilyn Sellars is an American country music singer known for her mezzo-soprano vocal range and traditional country style. She gained significant recognition in the mid-1970s with her hit single "One Day at a Time," which topped the country charts and secured a spot in the pop Top 40. Sellars' music is noted for its blend of country, pop, and gospel influences, featuring poignant lyrics and emotive delivery. Despite a relatively short recording career, her impactful contributions to the country genre earned her a place in music history.