I think many of the pro-abortion politicians have been excommunicated “latae sententae” (automatically), by the very fact that through their actions, they have facilitated abortions. Their public and legislative support of the abortion law, refusing to support efforts to abolish this invalid law, means that they have had a hand in abortions. No letter from a bishop, or the Pope, or anyone else is required for them to be excommunicated. They are so, ipso facto, i.e., by the very act that they have performed in their support of abortion laws.
What needs to happen for them is for them to repent, go to Confession, and be reconciled with the Church and Christ before they die. Otherwise, they’ll experience a “hot time in the old town tonight,” forever.