Brian Sebring, 44, is accused of aggravated battery with a deadly weapon and carrying a concealed gun.
Sebring allegedly shot Alex Stephens in the thigh and buttocks outside Stephens’ home in Tampa, Florida on Monday.
Mr Stephens, 46, was treated in hospital for his wounds, but has since returned home.
The pair got into an argument in the comments section of a Facebook post about President Donald Trump.
Sebring, a married father of two and a pizza delivery driver, told the Tampa Bay Times he responded to a friend’s thoughts on voting rights for convicted criminals.
The registered Democrat said he wrote that if someone wants to voice an opinion “don’t do criminal activity, don’t get caught, be a productive member of society”.
Both he and Mr Stephens have criminal records, but Sebring has retained the right to vote.
Mr Stephens has been jailed for robbery and cocaine possession, while Sebring admitted battery and has attended anger management classes in the past.
Mr Stephens responded to Sebring’s post and the pair exchanged threats on Messenger.
Mr Stephens reportedly threatened to harm Sebring’s wife and son, sent Sebring his address and told him to “come on over” if he wanted a fight.
Sebring said he “just snapped and let primal rage take over” as he left work early, went home and armed himself with a semi-automatic rifle and pistol before heading to Mr Stephens’ home.
After he parked outside and sounded his car horn, Mr Stephens came out carrying what Sebring said looked like a knife.
Sebring fired, then drove home and handed himself in to police.
“I’m not a bad guy,” Sebring told the newspaper, “but I mean, this guy threatened to hurt my family, and I went off the deep end,” admitting it scares him that “I could lose my temper like that and do something so stupid”.
Sebring was arrested and has been released on a $9,500 (£7,436) bond.
Sebring said he is being trolled on social media and has “ruined his life”.
“Now my mother is too afraid to leave the house, my sons are afraid to walk to school or church, all because of some keyboard gangsters.”
In Florida, anyone convicted of a crime loses their voting rights, but that may change in November, when the issue is put to a vote.
If 60% of voters back a proposed constitutional amendment, most convicted criminals no longer in jail will be able to vote once more.