What major event contributed to Ronald Reagan’s election in 1980?

Ronald Reagan a Republican from California, took office following a landslide victory over Democratic incumbent President Jimmy Carter in the 1980 presidential election. ... The combination of tax cuts and an increase in defense spending led to budget deficits, and the federal debt increased significantly during Reagan's tenure

Explanation:

Reagan campaigned for increased defense spending, implementation of supply-side economic policies, and a balanced budget. His campaign was aided by Democratic dissatisfaction with Carter, the Iran hostage crisis, and a worsening economy at home marked by high unemployment and inflation.