The American Mustache Institute wants Sen. Angus King, I-Maine, to team up with other mustachioed senators to develop "legislation that encourages more Americans to consider the wisdom, health benefits and beauty enhancement of facial hair of all kinds."

King renewed attention to the topic of congressional facial hair when he took office this year. Sens. John Hoeven, R-N.D., and Tom Coburn, R-Okla., are the other mustachioed senators the group mentioned in an open letter to King on Monday. Coburn is actually a dual citizen, passing for barefaced most of the year but often growing a beard in winter.

Coincidentally, 2013 marks 100 years since the United States last had a president with facial hair. President Taft was the last.