Rep. Thaddeus McCotter (R-Mich.) declared Saturday he would not wage a write-in campaign, ending an uphill bid to keep his seat after failing to make the primary ballot last week.

“I have ended my write-in campaign in Michigan’s 11th Congressional District,” McCotter said in a statement posted on his website.

McCotter did not make the primary ballot when his campaign only turned in 244 valid signatures — far less than the 1,000 required by the secretary of state to run for Congress in Michigan. McCotter was dumbfounded, and Republicans were livid at their colleague for putting an otherwise safe GOP seat in play.

On Tuesday, McCotter announced he would attempt to win the primary as a write-in candidate — but his effort was short-lived. The state attorney general has launched a criminal investigation into McCotter’s signature petitions.

In his statement Saturday, McCotter said he could not aid the investigation and mount a write-in bid at the same time. He declared, “one can’t clean up a mess multitasking.”

“Honoring this promise does not allow me to continue a political write-in campaign,” McCotter said. “This decision is final, regardless of how swiftly the investigation is concluded.”

McCotter’s decision paves the way for former state Sen. Loren Bennett to run a write-in campaign for the seat. Bennett announced his campaign on Friday, complicating McCotter’s already difficult path to victory.  Bennett will attempt to defeat teacher Kerry Bentivolio, the only Republican on the 11th district primary ballot.

The 11th district is a Likely Republican seat, but there’s potential for the district to be competitive for Democrats depending on what happens in the GOP primary. It’s one of the reasons McCotter’s mishap irked House Republicans.

The quirky McCotter, known for his sarcastic wit, ended his decision with these words: “To those who unhappy at this news, I’m sorry; to those happy at this news, you’re welcome.”

McCotter is the 26th House Member to retire without seeking other office this cycle. To see who else is leaving, check out our Casualty List.