The STEADFAST Act redirects federal funding away from the presidential election campaign financing system toward a new grant program that provides money directly to states and territories for election security upgrades. Starting in 2026, states that meet certain requirements—including using paper ballots, verifying voter citizenship, and requiring photo identification at polling places—can apply for grants to purchase voting equipment, improve cybersecurity protections, secure electronic poll books, and modernize voting systems. The bill eliminates the existing presidential campaign fund, which allows taxpayers to check a box on their tax returns to finance presidential elections, and redirects those designated funds along with any remaining balance to the new Election Security Fund. States will receive grants proportional to their registered voter populations, with a 5 percent cap on administrative costs, and must publicly report how they spend the money. The legislation takes effect for tax years ending after December 31, 2025.