Congressional offices routinely use form letters to reply to constituent inquiries, but that the response was so dramatically out of date it's causing some embarrassment. On Tuesday, Pitts's office said mistakes were made and that that it had reached out to the constituent to apologize.

"Congressman Pitts responds to tens of thousands of constituent inquiries a year. Because it is impossible to draft a unique reply to each inquiry, language is often reused for similar responses. In this case, a double mistake was made. Language that should have been archived was included in a draft response. The response was then pulled from the queue because of the error, and then mistakenly sent almost a year later.

"Responding to tens of thousands of letters a year is a complicated process. Mistakes are both few and rare, but do sometimes occur. This one was particularly embarrassing. We have apologized to the constituent and are reviewing our internal process to make sure this sort of thing can't happen again," said Andrew Wimer, a spokesman for Pitts, in a statement.

Businesswoman Aryanna Strader, Pitts's Democratic opponent in November, has already seized on the flap in an email fundraising ask to supporters.

“Being this completely out of touch with such a major foreign policy matter is inexcusable,” she wrote, according to the blog Politics PA. “If we are ever going to change Congress, we must change who we send there. And that is why I am asking you to please make a $16 contribution to our campaign today.”