Now, Father Altman’s own bishop has weighed in.
CNA offers an update:
After a Wisconsin priest said in a viral video that no Catholic can be a Democrat, the priest’s bishop will attempt fraternal correction, and said Wednesday the priest has inflicted a “wound” upon the Church. A Texas bishop, however, has doubled down on his support for the priest.
“I am applying Gospel principles to the correction of Fr. Altman. ‘If your brother does something wrong to you, go to him. Talk alone to him and tell him what he has done. If he listens to you, you have kept your brother as a friend. But if he does not listen to you, take one or two others with you to talk to him.’ (Mt 18:15-16).”
“I have begun this process, not in the bright light of the public arena, but as the Gospel dictates, in private,” Bishop William Callahan of La Crosse said in a Sept. 9 statement.
Bishop Strickland, responding to this, issued a statement to CNA in which he continued to defend Father Altman. You can read that here. 
The bishop took the unusual step of posting a full statement on the matter on the diocesan website:
Fr. James Altman has become a social media phenomenon and is now a mainstream media story. The amount of calls and emails we are receiving at the Diocesan offices show how divisive he is. I am being pressured by both sides for a comment; one side holds him up as a hero or a prophet, the other side condemns him and vilifies him and demands I silence him.

As I review Fr. Altman’s latest video statement of 30 August 2020, I understand the undeniable truth that motivates his message. When we approach issues that are contradictory to the Faith and teachings of Jesus Christ and the Catholic Church, particularly on abortion and other life issues, we should invite dialogue and heart-felt conversion to the truth. Our approach must never seek to divide, isolate and condemn.

That being said it is not only the underlying truth that needs to be evaluated but also the manner of delivery and the tone of his message. Unfortunately, the tone Fr. Altman offers comes off as angry and judgmental, lacking any charity and in a way that causes scandal both in the Church and in society. His generalization and condemnation of entire groups of people is completely inappropriate and not in keeping with our values or the life of virtue.
I am applying Gospel principles to the correction of Fr. Altman. “If your brother does something wrong to you, go to him. Talk alone to him and tell him what he has done. If he listens to you, you have kept your brother as a friend. But if he does not listen to you, take one or two others with you to talk to him.” (Mt 18:15-16). I have begun this process, not in the bright light of the public arena, but as the Gospel dictates, in private. Canon law indicates that before penalties are imposed, we need to ensure that fraternal correction, rebuke or other means of pastoral solicitude will not be sufficient to repair the scandal (can. 1341).
Most people expect a decisive move from me, one way or another. Many suggest immediate penalties that will utterly silence him; others call for complete and unwavering support of his views. Canonical penalties are not far away if my attempts at fraternal correction do not work. I pray that Fr. Altman’s heart and eyes might be open to the error of his ways and that he might take steps to correct his behavior and heal the wound he has inflicted on the Body of Christ. Pray for me as I address this issue, and pray for Fr. Altman that he might hear and respond to my fraternal correction. Finally, please pray for the Church that we might seek the truth in charity and apply it in our daily actions.