Veteran Senator Orrin Hatch has announced he will not run for re-election this year.
The Utah Republican chairs the Senate Finance Committee and was instrumental in last month's passage of the big tax bill.
In a statement today via a short video, Hatch said, "Every good fighter knows when to hang up the gloves."
His departure could prompt former GOP presidential nominee Mitt Romney to run for his seat. President Trump had urged Hatch to run again.