The U.S. Constitution and federal statute fix the date for House and one-third of Senate elections on the first Tuesday after the first Monday in November of even-numbered years, establishing a firm legal baseline that has held without interruption since the 19th century. Trader consensus reflected in the 97.2% implied probability for a scheduled 2026 vote stems from this framework, combined with the absence of any unilateral presidential or executive authority to alter it and the practical requirements for congressional action plus state-level administration. Recent developments, including adjustments to some state primaries and special elections following redistricting litigation, have not altered the general-election timeline. Realistic scenarios that could still shift outcomes remain narrow, such as an extraordinary national emergency prompting a rare bipartisan legislative delay or widespread state-level disruptions from disasters or court orders.