So, département by département:
(reminder:
RASNAG = senators without a group; often independents or people who 'lost the whip', it is also where RN senators are, as they don't have enough to form a group
RN = rassemblement national = marine le pen
Rec = reconquête = eric zemmour
LR = les républicains = historic right
UDI = union démocrate indépendant = center-right
PRV = parti radical valoisien = used to be borloo
Hor = horizon = edouard philippe, former PM to Macron
Ren = renaissance = macron
Modem = mouvement démocrate = bayrou
PRG = parti radical de gauche = former allied of PS, then macronists then reunited with PRV then anti-macronist and now ... I don't know anymore...
PS = parti socialiste = historic left
MDC = mouvement des citoyens = one of the political heirs of jean-pierre chevènement, they refused to go with him to support macron; they now support cazeneuve
EELV = europe écologie les verts = greens
PCF = parti communiste français = communists
Ins = insoumis = mélenchon)
37, Indre-et-Loire (préfecture: Tours)
Incumbents: 2 LR, 1 center-right.
Major changes in the 2020 municipal election:
Tours (130,000 inhab) center-right => united-left (EELV)
Saint-Pierre-des-Corps (15,000) PCF => right-wing
Lists: RN, LR (with one incumbent), Hor-Ren (with the son of the right-wing incumbent at the head), united-left (PS-EELV-PCF), Insoumis.
Probability: 1 LR, 1 Hor, 1 PS
38, Isère
Incumbents: 2 LR, 1 EELV, 1 PS, 1 Ren
Major changes:
Fontaine (22,000) PCF => Modem
Meylan (17,000) LR => PS
Saint-Egreve (16,000) right => EELV
Lists: Rec, RN, LR-UDI (2 inc.),right-wing, centrist, Ren (inc.), center-left, united left (EELV-PCF-PS with Green incumbent), Insoumis
Probability: LR-UDI: 2, Ren or center-left: 1, united left: 2 (EELV + PCF).
39, Jura
Incumbents: 1 LR, 1 PRV
Major changes:
Lons-le-Saunier (17,000) LR => PS
Candidates (see upthread, when there are two seats, each voter has two votes): RN, right-wing, LR 1, LR 2, PRV (inc.), Hor, centrist, PS-PCF, Ins 1, Ins 2
Probability: 1-2 LR, 0-1 PRV.
40, Landes
Incumbents: 2 PS
Dax (20,000) PS => right-wing
Candidates: RN, LR, Ren, PS 1 (inc.), PS 2 (inc.), EELV, PCF 1, PCF 2, Ins
Probability: 2 PS
41, Loir-et-Cher
Incumbents: 1 Modem, 1 UDI
Candidates: RN, LR-UDI, UDI-LR, Re, centrist-Re, centrist, PS, EELV-PCF
Probability: 1 LR, 1 UDI (but 1 centrist might be closing in and if LR, centrists and the left are still divided on the second round, one PS might get through, but it will be hard)
42, Loire
Incumbents: 2 LR, 1 PS, 1 PCF
Firminy (17,000) former PCF => LR
Rive-de-Gier (15,000) LR => PCF
Lists: RN, LR, right-wing (supported by Ren), PS, EELV, PCF, Ins
Probability: 2 LR, 0-1 right-wing, 0-1 PCF, 0-1 PS (last time PCF was ahead of PS)
43, Haute-Loire
Incumbents: 1 UDI, 1 LR
Candidates: RN, LR (inc.), UDI (inc.), Ins
Probability: 1 UDI, 1 LR
44, Loire-Atlantique
Incumbents: 1 LR, 1 Hor, 2 PS, 1 former EELV (still allied)
Orvault (27,000) right => left
Bouguenais (20,000) PS => LR
Lists: RN, LR-UDI (inc.), Hor (inc.), former PS, united-left (headed by inc. former EELV, with PS, EELV and PCF), Ins
Probability: 1 LR, 1-2 Hor, 2-3 united left (so 1 former EELV, 1 PS and maybe 1 EELV), 0-1 former PS
45, Loiret
Incumbents: 2 LR, 1 PS
Fleury-les-Aubrais (22,000) UDI => PS
Lists: RN, LR-UDI, Hor, PS-PCF, Ins-EELV
Probability: 1-2 LR-UDI, 0-1 Hor, 0-1 PS-PCF (PS)
46, Lot
Incumbents: 1 PS, 1 PRV
Candidates: LR, PRV-Re, Re, PRG, PS-EELV (inc), PS-EELV, former PS, PCF
Probability: 1-2 PS, 0-1 PRV-Re
47, Lot-et-Garonne
Incumbents: 1 UDI, 1 LR
Villeneuve-sur-Lot (23,000) PS => LR
Marmande (18,000) Hor => PS
Candidates: RN, LR (inc), UDI (inc), center-right, Re, PS, EELV, PCF, Ins 1, Ins 2
Probability: 1 UDI, 1 LR
48, Lozère
Incumbent: 1 PS (sits with RDSE grouping, as did the former senator she replaced in 2020)
Candidates: right wing, PS (inc), PCF-EELV, Ins
Probability: 1 PS or maybe right-wing if the others from the left maintain their candidacy in the second round
49, Maine-et-Loire
Incumbents: 2 LR, 1 Hor, 1 PS
Lists: RN, LR-UDI (1 inc), right-wing, Hor (inc), PS, former-PS-EELV, Ins
Probability: 2-3 LR-UDI, 1-2 Hor, 0-1 former-PS-EELV, 0-1 PS
The left will probably pay their division
50, Manche
Incumbents: 2 LR, 1 PS
Granville (12,000) right => left
Lists: RN, LR (2 inc.), right-wing, Hor-Ren, (former)Hor-Ren, PS-PCF, EELV, Ins
Probability: 1-2 LR, 0-1 Hor-Ren, 1 PS
51, Marne
Incumbents: 2 UDI, 1 LR
Lists: RN, LR-UDI, Hor, PS-PCF-EELV, Ins, former-EELV
Probability: 2-3 LR-UDI (1 right, 1 UDI, maybe 1 LR), 0-1 Hor,
RN might not be so far off
52, Haute-Marne
Incumbents: 2 LR
Candidates: RN, LR1 (inc), LR2, right-wing 1, right-wing 2, centrist, PRG, Ins1, Ins2
Probability: 2 LR
53, Mayenne
Incumbents: 1 UDI, 1 LR
Candidates: RN, LR (inc), UDI1 (inc), UDI2, PS, EELV, Ins.
Probability: 1-2 UDI, 0-1 LR (but probably both incumbents reelected)
54, Meurthe-et-Moselle
Incumbents: 2 LR, 1 PRV, 1 PS
Nancy (105,000): PRV => PS
Lists: RN, right-wing, LR-PRV (2 inc), ecologists, PS-PCF (Inc), Ins
Probability: 2-3 LR-PRV (1 LR, 1 PRV, maybe 1 LR), 1-2 PS-PCF (1 PS, maybe 1 PCF)
55, Meuse
Incumbents: 1 LR, 1 PRV
Candidates: RN, LR, PRV (inc), right-wing1, right-wing2, centrist, PS, Ins
Probability: who knows in this very rural part of the world. 2 right-wing senators anyway.
56, Morbihan
Incumbents: 1 LR, 1 UDI, 1 former EELV
Lorient (57,000) PS => UDI
Lists: RN, right-wing, LR, center-right, PS-PCF, left-EELV, Ins
Probability: 1-2 LR, 1-2 center-right, 0-1 PS-PCF, 0-1 left-EELV.
57, Moselle
Incumbents: 1 RASNAG, 1 LR, 1 UDI, 1 center-right, 1 PS
Metz (116,000) PS => LR
Forbach (21,000) PS => LR
Lists: RN, LR-UDI (2 incumbents), right-wing1 (1 incumbent), right-wing2, PRV, center-right, Hor, left-wing, PS, RDG-PCF, 2 independents
Probability: with that much division, it is tough to predict. LR-UDI might keep two, but barely. RN might get 1. There will be at least 1 seat in the center-right, and PS might keep theirs although it will be hard.
58, Nièvre
Incumbents: 1 UDI, 1 PS
Varennes-Vauzelle (9,000) right => PCF
Candidates: RN, UDI-LR (inc), Re1, Re2, centrist-ecologist, left-wing, PS1 (inc), PS2, PCF, EELV1, EELV2, Ins1, Ins2, independent
Probability: 1 UDI-LR, 0-1 PS, 0-1 Re1 (an MP), but I'd say the most probable is status quo.
59, Nord
Incumbents: 2 LR, 2 UDI, 2 right-wing, 1 Re, 2 PS, 2 PCF
Faches-Thumesnil (17,000) UDI => Ins
Bailleul (14,000) center-right => center-left
Seclin (12,000) PCF => right-wing
Lists: Rec, RN, LR (2 inc), UDI (1 inc), right-wing1 (2 inc but one in last position), former UDI1 (supported by other UDI inc), former UDI2, right-wing2, right-wing3, Hor, Re, former-PS (1 inc), PS (1 inc), PCF (2 inc), EELV, Ins
Probability: the left will be happy to keep four, there's no guarantee. 1 PS is guaranteed, I believe they'll get 2. 1 PCF is guaranteed, they might get two thanks to divisions everywhere. The former-PS incumbent might get 1 but I don't think so.
On the right, LR will be happy to keep 1, there will be at least 1 UDI (but which one ??), and probably 2 right-wing1. There will be a battle between Hor and Re for 1 seat. Then, there could be second seats or first seats for any other right-wing list...
60, Oise
Incumbents: 3 LR, 1 PS
Lists: RN, LR1 (inc), LR2 (inc), LR3 (inc), centrist, Re-Hor, PS-PCF-EELV, Ins
As there are 3 male incumbent LR senators, they couldn't be all elected in 1 list (they need to alternate male-female and could only be 1st, 3rd and 5th, wth four senators elected). It can prove risky with a united left list that could keep the PS seat and a united Re-Hor and a centrist list.
Probability: 1-3 LR, 0-1 PS, 0-1 centrist, 0-1 Re-Hor
61, Orne
Incumbents: 1 LR, 1 UDI
Candidates: RN, LR (inc), UDI-Re (inc), Hor, PS, EELV, PCF, Ins
Probability: 1 LR, 1 UDI
62, Pas-de-Calais
Incumbents: 1 LR, 1 UDI, 1 Modem, 1 Re (elected as PS), 1 MDC, 1 former PS, 1 PCF
Bruay-la-Buissière (21,000) left => RN
Lists: RN, LR-UDI (2 inc), Hor, Modem-Re (1 modem inc), PS-MDC (1 MDC inc), PCF-left (1 PCF and 1 former PS inc), EELV, Ins
Probability: 0-1 RN, 1-2 LR-UDI, 1-2 Modem-Re, 2 PS-MDC, 1-2 PCF-left
63, Puy-de-Dôme
Incumbents: 1 LR, 1 center-left, 1 PS
Lists: RN, LR (inc), UDI, center-left-PRG (inc), PS-PCF-EELV, Ins
Probability: 0-1 LR, 1 UDI, 0-1 center-left, 0-1 PS-PCF-EELV
64, Pyrénées-Atlantiques
Incumbents: 1 LR, 1 Modem, 1 PS
Biarritz (25,000): Modem => LR
Lists: Rec, RN, LR (inc), Modem (inc), PS (inc), PCF, EELV, Ins, 1 independent
Probability: 1-2 LR, 1 Modem, 0-1 PS
65, Hautes-Pyrénées
Incumbents: 1 PRG, 1 PS
Candidates: RN, LR, Hor, centrist, PRG (inc), PS (inc), EELV, PCF1, PCF2, Ins
Probability: 1 PRG, 1 PS
66, Pyrénées-Orientales
Incumbents: 2 LR
Perpignan (120,000) LR => RN
Candidates: far-right, RN1, RN2, LR1 (inc), LR2, PS, EELV, PCF, LFI
Probability: 1-2 LR, 0-1 RN, 0-1 PS
75, Paris
Incumbents: 2 LR, 2 former LR, 1 Re, 1 former EELV, 2 former PS, 3 PS, 1 PCF
Lists: LR (1 inc), right-wing1 (1 LR inc), right-wing2, Re-Modem-Hor, PS-PCF-EELV (3 inc), Ins, 2 independents
Probability: the united left will probably get 7-8 seats (3 PS, 2-3 EELV, 1 former PS inc, 1 PCF), 0-1 Re, and the rest between the right-wing LR lists.
77, Seine-et-Marne
Incumbents: 3 LR, 1 UDI, 1 Hor, 1 PS
Villeparisis (26,000) LR => PS
Lists: RN, LR (3 inc), right-wing1, right-wing2, PRV, Hor-Re, PS-EELV-PCF, Ins
Probability: 3-4 LR, 1-2 PS-EELV-PCF (which would be 1 PS and 0-1 PCF), and then seats among the centrists and right-wing, probably 1 Hor-Re
78, Yvelines
Incumbents: 4 LR, 1 UDI, 1 Re
Houilles (32,000) right => Re
Le Chesnay-Rocquencourt (31,000) right => Modem
Lists: RN, right-wing, LR-UDI (5 inc. including current president of the Senate Gérard Larcher), center-right, Ren-Hor-Modem (inc), EELV-PS-PCF, Ins, 1 independent
Probability: 5-6 LR-UDI, 0-1 Re, 0-1 EELV
91, Essonne
Incumbents: 2 LR, 2 UDI, 1 Modem
Corbeil-Essonnes (51,000) LR => PCF
Savigny-sur-Orge (36,000) LR => EELV
Athis-Mons (34,000) LR => PS
Lists: RN, LR (1 inc), right-wing (1 LR inc), UDI (2 inc), Modem-Ren-Hor (inc), centrist, PS-PCF-EELV, Ins
Probability: 1-2 LR or former LR, 1-2 UDI, 0-1 Modem, 1-2 PS-PCF-EELV (1 PS + 0-1 PCF)
92, Hauts-de-Seine
Incumbents: 3 LR, 1 UDI, 2 Re (1 elected as PS in 2017, 1 elected as EELV in 2011, reelected as En Marche in 2017), 1 PCF
Colombes (85,000) LR => EELV
Châtillon (36,000) LR => PS
Lists: RN, LR (3 inc), former LR, UDI (inc), Re-Hor (1 inc), PCF-EELV-PS (1 inc), Ins, 1 independent
Probability: 2-3 LR, 0-1 former LR, 1 UDI, 1 Re-Hor, 1-2 PCF-EELV-PS (1 PCF, 0-1 EELV)
93, Seine-Saint-Denis
Incumbents: 2 LR, 1 UDI, 1 PS, 2 PCF
Saint-Denis (112,000) PCF => PS
Aubervilliers (88,000) PCF => UDI
Bondy (54,000) PS => LR
Bobigny (54,000) UDI => PCF
Saint-Ouen-sur-Seine (50,000) UDI => PS
Noisy-le-Sec (44,000) UDI => PCF
Lists: Rec, RN, LR (1 inc), UDI (1 inc), PRV, PRG, PS-EELV, PCF (1 inc), Ins, 2 independents
Probability: 2 LR, 1 UDI, 2 PS, 1 PCF
94, Val-de-Marne
Incumbents: 2 LR, 1 UDI, 1 EELV, 2 PCF
Champigny-sur-Marne (77,000) PCF => LR
Villejuif (54,000) LR => PCF
Choisy-le-Roi (45,000) PCF => LR
Villeneuve-Saint-Georges (33,000) PCF => right
Lists: RN, LR-UDI (1 LR inc), former-UDI-Hor-Modem (1 UDI inc), PCF-PS (1 PCF inc, + 1 PS inc from Oise), former-PS-EELV, Ins, 2 independents
Probability: 2 LR-UDI, 1-2 formerUDI-Hor-Modem, 1-2 PCF-PS (1 PCF + 0-1 PS), 0-1 former-PS-EELV (0-1 former PS)
95, Val-d'Oise
Incumbents: 1 Rec (elected as former LR), 2 LR, 1 Re (elected in 2011 as PS, in 2017 as En marche), 1 PS
Lists: Rec (inc), RN, LR (2 inc), UDI-Hor, Re (inc), PS-PRG (Inc), PCF-Ins-EELV, left-wing
Probability: 2-3 LR, 0-1 Rec, 0-1 UDI-Hor, 0-1 Re, 0-1 PS