Michael G. Mosteller II is the Democratic candidate for the West Virginia House of Delegates in District 21. He is a husband and father of two who lives in Putnam County. Mosteller previously ran for the House in 2024 and is running again in 2026. His campaign says his interest in politics grew after the 2014 Elk River chemical spill, when he became involved in efforts to improve protections around above-ground storage tanks. Mosteller says he authored the Above Ground Storage Tank Act as a private citizen after the spill, and the Legislature later passed the bill into law. His campaign also points to concerns about the opioid crisis and education as reasons he became more involved in politics. Mosteller has made environmental protection, drinking water, education, health care and reproductive rights part of his campaign. He won the Democratic nomination in the May 2026 primary and will face Republican C.D. Caldwell in November. The race is for an open seat because current District 21 Republican Delegate Jarred Cannon is not seeking reelection.