ANALYSIS — Michigan Democrat Gary Peters won’t be the only senator to retire this cycle, at least according to almost a century of history.
Whether it’s age or opportunity, political pressure or personal circumstances, at least two senators have left the chamber every cycle, going back to at least 1930. In fact, there’s been an average of at least five open Senate seats each election year since Herbert Hoover was president and there were only 48 states in the union.
More recently, the number of open Senate seats has varied from nine in 2024 to as few as three in 2018 and four in 2020. And typically, no party is spared. Both Republicans and Democrats have had at least one open Senate seat in 43 of the past 48 election cycles. The last time a party didn’t have an open seat was 2018, when every Democratic incumbent who was up that year ran for reelection.
