Over 94% of teacher's union donations since 1990 have gone to the Democrats:
https://www.opensecrets.org/industries/totals.php?ind=L1300
https://njump.me/nevent1qqspks062cczcahak7d67lx9em8jr89nuvlh5kjmgglcy46nkcxaajczyzqme57nrqeu8pg2c54varu3mqk7qshfxttmk8aqmvm9m67x34cy7xt373e