This question resolves YES if, at any time before 2039, a sitting US Governor, Senator, President, or Vice President:
Is openly is engaged in multiple relationships, with the consent of all parties involved (ie: no cheating)
These relationships are acknowleged as polyamorous by the politician or are uncontroversially regarded as such by the media.
This becoming known does not result in a major scandal: The politician must not resign due to this becoming known, or lose re-election by a significant margin because of this becoming known. They must also not decline to seek re-election solely because the fall-out of this becoming known has obviously tanked their chances of re-election.
Otherwise, this question resolves NO.
Fine print:
If the structure of the US government, or any state government, is modified to replace any of these offices (such as if a state or the federal government introduces a "Prime Minister" position), or if offices of similar prestige are introduced (such as a state or the federal government introducing a council-style executive branch), politicians who hold these new offices count for resolution of this question.