SD-S2 · MODEL v1.14 · 2 INPUTS MEASURED
SD-S2 enters through the Republican-held flip route at 3.4 with 65% of the component weight available: statewide competitiveness, incumbent cash vulnerability.
THE MEMBER
Mike Rounds is the Republican senator in SD Class 2. The retained roster records 11.6 cumulative years of Senate service through the source cutoff; the seat is next contested in 2026.
R000605THE STATE
SD recorded a R+29.2 presidential margin statewide in 2024. The senator reported $2,736,664 cash on hand through 2026-06-30.
SCORE ANATOMY
The statewide 2024 presidential result was R+29.2. A tied state begins at 100 and each Republican margin point subtracts four points.
Not in this score
Not applicable to this Republican-held route; no Democratic-primary value is imputed.
Not in this score
Not used in this route; the retained AIPAC model covers the Democratic House field.
Not in this score
Not used in this route because the retained alignment trackers cover the Democratic caucus.
The FEC candidate summary reports $2,736,664 cash on hand through 2026-06-30. The inverse log scale is 100 at $50,000 or less and 0 at $5 million or more.
Not in this score
No retained state-legislative Democratic primary catalog records uncontested contests for this state, so the component is omitted and the available weight is renormalized.
SENATE TERM
Formula renormalized(0.45 × competitiveness + 0.20 × cash vulnerability + 0.15 × local context + 0.20 × state contestation) × (0.6 + 0.4 × 0.65)
Source cutoff Aug 4, 2026 · How the score is built · Source ledger · Factual seat record