Jan 3, 1997
Collins Takes Office
Susan Collins is sworn in as U.S. Senator from Maine, beginning a tenure that would make her one of the most durable Republican incumbents in the country.
Source: U.S. Senate
history
Nov 8, 2016
Maine Adopts RCV
Maine voters pass a citizen-initiated referendum adopting ranked-choice voting for federal and state primary elections — the first state in the nation to do so.
Source: Maine Secretary of State
history
Nov 3, 2020
Collins Wins Fifth Term
Despite heavy Democratic spending and a nationally watched contest, Susan Collins defeats Democrat Sara Gideon 51%–42%, overcoming predictions of a close race.
Source: Maine Secretary of State
history
Jan 1, 2025
2026 Cycle Opens
With Collins up for re-election in 2026, national Democrats begin recruiting candidates for what they view as a critical pickup opportunity on the path to Senate majority.
Source: Editorial
cycle
Jul 7, 2026
Politico Publishes Allegations
Politico publishes a report detailing sexual assault allegations against Democratic primary candidate Graham Platner, reshaping the primary contest.
Source: Politico / WLOS
crisis
Jul 7, 2026
Gov. Mills Calls for Withdrawal
Maine Governor Janet Mills publicly calls on Graham Platner to withdraw from the U.S. Senate Democratic primary, citing the allegations. Maine Democratic Party leadership aligns with Mills.
Source: WLOS
crisis