Come next January there could be a record low six or fewer states whose U.S. Senators do not share the same partisan affiliation

As the partisan divide seemingly widens cycle-to-cycle and the number of battleground states wanes, Smart Politics continues to track the decline in the number of split U.S. Senate delegations, which currently rests at an all-time low in the direct election era.

Ever since the 117th Congress convened following the 2020 election, there have been just seven states with a pair of senators who do not share the same party identification.

Those current seven states are Arizona (Democrat Mark Kelly and independent Kyrsten Sinema), Maine (Republican Susan Collins and independent Angus King), Montana (Democrat Jon Tester and Republican Steve Daines), Ohio (Democrat Sherrod Brown and Republican J.D. Vance), Vermont (independent Bernie Sanders and Democrat Peter Welch), West Virginia (newly minted independent Joe Manchin and Republican Shelley Moore Capito), and Wisconsin (Republican Ron Johnson and Democrat Tammy Baldwin).

That number has dropped from 19 states following the 2010 election and once peaked at 27 states after the 1978 midterms.

Each of the seven aforementioned states are holding U.S. Senate elections this November and one is all but certain to lose its split delegation status (West Virginia, with Republican Governor Jim Justice heavily favored).

That would reduce the number of split-delegation states to six.

Four additional states might also lose their split-delegation status.

Jon Tester and Sherrod Brown are the last remaining Democrats elected to state-wide office in Montana and Ohio respectively and will need split-ticket voting in their favor to remain in office.

Wisconsin Democrat Tammy Baldwin is in a stronger position to hold her seat given the Badger State’s more evenly divided partisan tilt.

Arizona’s open seat probably has a greater than even chance to go back to an all-Democratic delegation as U.S. Representative Reuben Gallego awaits the winner of the GOP primary, which is likely to be controversial 2022 gubernatorial nominee Kari Lake.

Current polling suggests many Democratic incumbents are not being dragged too badly by President Joe Biden’s dismal approval ratings, but a better than expected GOP turnout could turn four all-Democratic states into split delegations: open seat races in Maryland and Michigan as well as Nevada (Jacky Rosen) and Pennsylvania (Bob Casey).

An even more remote possibility is that an unexpected Democratic boost at the ballot box could put a halt to the all-Republican U.S. Senate delegations in Florida (Rick Scott) and Texas (Ted Cruz).

Vermont has the current longest split-delegation run dating back nearly 50 years to January 1975 with the election of Patrick Leahy.

Ohio owns the longest active Democratic-Republican split with each party holding one seat since January 2007.

South Carolina set the bar for that mark with a 40+ year run from September 1964 until January 2005, with most of these years represented by Strom Thurmond and Fritz Hollings.

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  1. Connor Cobb on June 3, 2024 at 8:57 pm

    There’s a possibility that ME, VT and WI might be the only split states if every state mirrors the presidential and no state changes from 2020.

    • Cecil Crusher on June 4, 2024 at 8:39 am

      Should the D Caucus lose its operational majority come early 01 2025, the failure of the national Democrats to oust R incumbents in ME in 2020 and WI in 2022 arguably will be at least as much to blame as the presumed loss of a West Virginia seat – and perhaps additional seats this cycle. After all, their nominee for president carried the Pine Tree State in ’20 and their nominee for governor carried the Badger State in ’22!

  2. Flickertail-Pembina on June 4, 2024 at 8:58 am

    OH also has several *D-held* seats on the Supreme Court thereof – which rather recently became partisan elective offices.

    Aside from ‘lost cause’ WV, the seats at the greatest risk of turnover may well be MT, OH, NV, and MI (the Free State has too steep of a pro-Democratic tilt at the presidential level, and the recent intramural discord between the nominee and the cult-like apparachiks who now firmly control the national organization has hardly augmented the prospects for the MAGA-flavored party in that state; the Keystone State has already rejected an aspiring carpetbagger from NJ – ‘North Jersey’, at that! – two years ago. Will its voters be more willing to vote one from the Gold Coast of CT in?).

  3. Cecil Crusher on June 6, 2024 at 12:13 am

    Most prognosticators had the Copper State as the milieu where an incumbent would stand for re-election as an independent contender, resulting in a volatile three-sided contest (it may yet happen in the Mountain State as well).

    Should “Gold Bars Bob” be re-elected to his fourth 6-year term – an extremely remote chance to be sure, even with no conviction – the Garden State will have a “split” delegation in early 2025 (the state most recently had such a pairing with Republicans governors filling vacancies on ‘partisan bases’ of Democratic-held seats, in 2013 and 1982).

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