How many seats do Republicans and Democrats hold in the 2025 Senate and how many are up for reelection in 2026?
Executive summary
Republicans hold a 53‑seat majority in the 119th Senate while Democrats (including two independents who caucus with them) make up the remaining 47 seats (45 Democrats + 2 Independents) — Senate.gov lists the 119th Congress as Republicans 53, Democrats 45, Others 2 for a 100‑seat chamber [1] [2]. Between regularly scheduled contests and special elections, 35 Senate seats will be contested in 2026 — a map that includes 22–23 seats held by Republicans and 12–13 held by Democrats depending on the tracker — with special elections in Florida and Ohio to fill shortened terms (multiple sources: [6]; [7]; [5]; [12]0).
1. The current arithmetic: who sits where in 2025
Official Senate sources list the party division for the 119th Congress as Republicans 53, Democrats 45 and Independents 2 for a total of 100 seats; the Senate website and its party‑division page are explicit about the 53‑seat Republican majority [2] [1]. Independent senators are counted separately on party lists but in practice both independents caucus with Democrats in the current Congress according to reporting [3] [4].
2. How many seats are up in 2026 — regulars plus specials
Most analysts and trackers show 35 Senate contests on the 2026 ballot: the usual Class II roster (about one‑third of the chamber) plus two additional special elections to complete vacancies in Ohio and Florida caused by resignations and subsequent appointments [5] [6] [7]. Sources vary slightly on the party breakdown of those 35 seats — but they converge on 35 total contests [6] [8].
3. Who is defending those seats — Republicans have most to lose
Analysts’ early tallies put 22–23 of the 35 seats as currently held by Republicans and 12–13 as held by Democrats, meaning Democrats need a net gain of four seats to retake the majority if trackers’ counts hold [6] [8] [7]. Multiple forecasters and nonprofits underline that Republicans face the bulk of the 2026 map [6] [8].
4. Why special elections in Florida and Ohio matter
Both Florida’s Class 3 seat and Ohio’s Class 3 seat were filled by gubernatorial appointments after senators resigned in 2025; those appointees will face special elections in 2026 to complete the remaining terms, so the 2026 ballot will include those two additional contests beyond the routine Class II slate [5] [9]. These specials slightly shift the tally of seats in play and are singled out by trackers and Wikipedia’s 2026 election summary [5] [9].
5. Differences among trackers and why counts vary
Trackers such as 270toWin, Council for a Livable World and Sabato’s Crystal Ball agree on the 35 contests but report small differences in how many of those seats each party currently holds (for example, 270toWin reports 23 Republican‑held seats up; Council for a Livable World reports 22 Republican seats up) — discrepancies stem from how each source treats appointed seats, independents, and timing of resignations or retirements [7] [6] [10] [8]. These operational choices explain the one‑seat spread in summaries.
6. The immediate arithmetic for control and the path forward
Given the current 53‑seat Republican majority, Democrats must net at least four seats in the 35 contests to obtain a 51‑seat majority (a net‑4 gain from 47 to 51), a threshold emphasized across forecasts and analysis [8] [6]. Political analysts stress the difficulty: the 2026 map has a disproportionate number of Republican‑held seats in states that lean strongly Republican, though pockets of competitiveness exist [6] [11].
7. What the reporting does not say (limitations)
Available sources disagree slightly on whether 22 or 23 Republican seats are up and therefore on exactly how many Democratic seats are on the ballot; they consistently report 35 total contests but differ in small tallies because of appointment timing and classification of independents [6] [7] [8]. Available sources do not mention a single, universally accepted line‑by‑line roster that fixes the party holding each of the 35 seats without any variation across trackers — readers should expect a one‑seat variance among reputable trackers [6] [7].
8. Bottom line for readers and partisans
The Senate starts 2025 with Republicans holding 53 seats and Democrats (plus two Democratic‑caucusing independents) holding 47 [2] [1]. The 2026 elections will be unusually consequential: 35 seats are in play, including two specials in Florida and Ohio, and Republicans are defending the lion’s share of them — meaning Democrats face an uphill but clearly defined path to a Senate majority [6] [5] [8].