The Summit County panel found Richard James Beasley, 53, guilty of aggravated murder, meaning he will be eligible for the death penalty, the Akron Beacon Journal reported.
Prosecutors had told jurors Monday that while they had no DNA evidence tying Beasley to any of the killings, they had a criminal imprint that linked him to all four shootings, the newspaper said.
In his closing argument, Summit County Assistant Prosecutor Jonathan Baumoel urged jurors to use common sense, saying Beasley used "a systematic approach to executing these men" with a "clear method of operation."
Beasley was charged with multiple counts of aggravated murder and attempted murder in the 2011 shootings in which Ralph Geiger, 56, of Akron; David Pauley, 51, of Norfolk, Va.; and Timothy Kern, 47, of Massillon, Ohio, were killed and Scott William Davis, 48, was wounded.
Beasley's co-defendant, Brogan Rafferty, 18, of Stow was convicted in October and faces life in prison.
Davis was the state's key witness against Beasley, the Beacon Journal said.
Baumoel said Beasley was "the mastermind" of the plot using the free website Craigslist to advertise a non-existent job to prey on unemployed men. His shooting method -- all of the victims were shot from behind -- was "like DNA," Baumoel said.
Lead defense attorney James Burdon challenged Davis' testimony, suggesting he had ties to a motorcycle club and was sent to Ohio as a hit man.
Beasley testified in his own defense, saying he was an informant on biker activities for Akron police and that Davis was sent to Ohio to kill him, Burdon said.