who you elected — split license.

Roster and roll-call VOTE records (the derived compilation) are dedicated to the public domain under CC0 1.0 Universal:
https://creativecommons.org/publicdomain/zero/1.0/
The underlying government roll-call and roster records are U.S. public records.

Campaign-finance and individual-donor data are NOT under CC0. They are derived from U.S. Federal Election Commission records and carry a federal restriction (52 U.S.C. 30111(a)(4); 11 CFR 104.15): attribution, no commercial use, no use to solicit contributions. See:
https://whoyouelected.org/licenses/fec-restricted