“I just ended my political career,” Mr. Gravel said at the party’s convention. “From 15 years old to now, my political career is over, and it’s no big deal.”

Mr. Gravel, 78, spent 12 years in the United States Senate from Alaska, pursuing even then an anti-war agenda and railing against the military industrial complex. His tenure was marked by dramatic procedural actions criticizing the Vietnam War, but his claim to fame came when he tried to release the Pentagon Papers by reading them on the Senate floor. He also waged a one-man filibuster that ultimately led to a compromise to let the draft expire in 1973. He lost his seat in 1980, after a contentious Democratic primary.

He lost the Dem nomination and now the Libertarian–this could well be Gravel’s last hurrah.