Democrat Jim Barksdale slammed Sen. Johnny Isakson this week over the scuttled appointment of a Latino judge to a spot on the federal bench, saying the Republican should have fought harder to convince colleagues to support him.

The judge's top adviser, though, called Isakson a "true statesman" and thanked the incumbent for his support.

DeKalb State Court Judge Dax Lopez' nomination was scuttled in January by U.S. Sen. David Perdue over concerns about his past membership on the board of the Georgia Association of Latino Elected Officials. That same criticism haunted him after he was nominated for a seat on the Georgia Supreme Court bench; Lopez has since pulled his name from the running.

Isakson infuriated some Republicans when he called for a hearing for Lopez' appointment. After Lopez' nomination was blocked, the two-term incumbent said he respected Perdue's decision but he was "disappointed" that Lopez never got a chance to tell his story.

Barksdale, a political newcomer who has pumped $3 million into his Senate bid, senses a soft spot in his bid to unseat Isakson in November.

“Where’s Johnny?” Barksdale campaign manager Dave Hoffman said. “Georgians need a U.S. senator that will do their job and stand up for what is right.”

Fred Hicks, Lopez' judicial campaign manager, defended Isakson's handling of the judge's nomination.

"Sen. Isakson is a true statesman, a true gentleman and has been very supportive of Judge Lopez and has valued the opinion of the legal community on judicial matters," said Hicks. "We feel that he has been very respectful and has fulfilled his duties as a senator."

More: Latino judge faced stiff opposition to seat on Georgia's top court