Another candidate is considering a write-in bid for the GOP nomination to succeed retiring Rep. Thaddeus McCotter (R), stoking speculation that Republicans will not be able to settle on a consensus successor.

Former state Sen. Nancy Cassis told the Associated Press on Tuesday that she’s interested in running as a write-in on the Aug. 7 GOP primary ballot, joining a burgeoning field of potential candidates.

McCotter announced his retirement on Saturday after he failed to make the GOP primary ballot. There were so many errors with his signed petitions that the Michigan attorney general launched a criminal investigation.

McCotter’s withdrawal left an unknown Republican as the sole candidate on the primary ballot: reindeer rancher Kerry Bentivolio. Michigan Republicans are trying to decide whether to support Bentivolio or back a write-in candidate with more political experience.

If Republicans back a write-in, they might have several options. Former state Sen. Loren Bennett announced Friday that he’s running as a write-in candidate. In addition, former House aide Paul Welday, former state Rep. Rocky Raczkowski and Oakland County District Court Judge Kimberly Small have expressed interest in running as write-in candidates.

But local GOP operatives agree that more than one write-in candidate would split the party vote and defeat the purpose.

There are two Democrats on the primary ballot: internist Syed Taj and William Roberts, a Lyndon LaRouche supporter. But Democrats are clearly supporting Taj, and the local party already gave him its official backing.