DETROIT (AP) -- U.S. Rep. John Conyers, No. 2 in seniority in the House, lost his appeal Friday to get on the August primary ballot after Michigan election officials found problems with the Democrat's nominating petitions.
The Secretary of State's office affirmed a decision by Detroit-area election officials to keep Conyers off the ballot.
The ruling puts his 50-year congressional career in jeopardy unless courts intervene or he runs a successful write-in campaign. Conyers would mount a write-in effort if necessary in the heavily Democratic district, his campaign manager has said.
There is precedent in Michigan for such an effort. Detroit Mayor Mike Duggan launched a successful write-in campaign in last year's primary after his name was kept off the ballot due to a residency issue.
Conyers also has mounted a legal challenge to have the Michigan election law at the heart of the dispute declared unconstitutional, and a federal judge is expected to rule later Friday.
"The Secretary of State made her decision, and we'll live with it," said Bert Johnson, Conyers' campaign chair and a Democratic state senator. "Obviously, we disagree, and we'll wait for the federal court to rule."
Conyers, 85, had appealed to the state after Wayne County officials said there were problems with some people who collected signatures. The circulators weren't registered to vote or had listed a wrong registration address.
That can spoil petitions, under Michigan law, and as a result Conyers lacked the 1,000 signatures necessary to get on the ballot.
"A circulator's failure to register is a fatal defect that renders all signatures appearing on a petition he or she circulated invalid," the Secretary of State's review said Friday.
Ending Conyers' career that way would be "pretty outrageous," his lawyer, John Pirich, said this week.
Political opponents said Conyers should follow election procedures like other candidates. An attorney for a Democratic challenger, the Rev. Horace Sheffield III, said Conyers for decades had no problem following the law.
"In essence, they played the game, lost and then complained that the rules were unfair," Eric Doster said, quoting a Virginia judge.
Conyers was elected to the U.S. House in 1964 after winning the Democratic primary by 108 votes.
Since then, he routinely has won re-election -- often with more than 80 percent of the vote -- and became the senior member of the Congressional Black Caucus, which he helped found. He won in in 2012 with 83 percent of the vote.
In 2012, another Michigan congressman, Republican Thad McCotter of suburban Detroit, didn't make the ballot because a staff member turned in phony signatures or ones from old petitions. McCotter announced he would mount a write-in campaign but later dropped the effort.
The most important national case of a successful write-in campaign was in 2010, when Alaska Republican Sen. Lisa Murkowski won re-election using that method after she was defeated by a tea party candidate in the Republican primary.