I’ve sent this letter to Senators Ernst and Grassley. It charitably overestimates their willingness to put country above party, but it was worth a shot.
There are those who say that the Republican Party has become a cult of personality, and the personality is Donald J. Trump. They say that the Republican Party has abandoned principles it once fought for, including respect for the rule of law, adherence to the Constitution, and upholding personal accountability, to defend Trump. There are those who say the Republican Party has lost its honor, and that Republican Senators are Trump lackeys, incapable of voting to remove Trump from office no matter the facts and no matter the law.
I am not one of those people. I think you can look past the politics of the moment and remember that you took an oath:
I do solemnly swear (or affirm) that I will support and defend the Constitution of the United States against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; that I take this obligation freely, without any mental reservation or purpose of evasion; and that I will well and faithfully discharge the duties of the office on which I am about to enter: So help me God.
Because I think you can in fact remember your sworn duty at this moment, I also think you can look at the uncontested facts presented in public under oath in the impeachment hearings, and vote to convict Trump.
If, on the other hand, you would like to convince me that the Republican Party should be permanently discredited and dishonored, by all means vote to acquit. It is your own honor at stake, so choose well.