MegaParsec Q

parseGACandAndParty :: Parser (Text, ET.PartyT)
parseGACandAndParty = parseCP
  where
    atEnd p = p >>= \res -> do { MP.eof; return res}
    parseP :: Parser ET.PartyT = parseParty . toText <$> (MP.between (MP.char '(') (MP.char ')') (MP.some MP.letterChar))
    parseCP :: Parser (Text, ET.PartyT) = first toText <$> MP.someTill_ (MP.asciiChar <|> MP.spaceChar) (atEnd parseP)

----

"Sheila Clark Nelson (I) (Dem)"

---

 MegaParsec (parseTXRace): mpToCsv:1:24:
                                                                                                                                                                                                                                                                                                                                                    |
                                                                                                                                                                                                                                                                                                                                                  1 | Sheila Clark Nelson (I) (Dem)
                                                                                                                                                                                                                                                                                                                                                    |                        ^
                                                                                                                                                                                                                                                                                                                                                  unexpected space
                                                                                                                                                                                                                                                                                                                                                  expecting end of input