By Joseph Ax and Jim Finkle
(Reuters) - Georgia Secretary of State Brian Kemp, the Republican candidate in Tuesday's hotly contested gubernatorial election, has opened a probe of the state Democratic Party over what his office alleged on Sunday was a failed attempt to hack voter registration systems.
Kemp's office, which supervises elections in Georgia, offered no evidence publicly for launching the investigation two days before voters go to the polls to decide which party will control Congress and to select three dozen state governors.
The race between Kemp and Democrat Stacey Abrams, who is vying to become the nation's first black female governor, has become a flashpoint for allegations of voter suppression.
Kemp's office said in a statement on Sunday it opened the investigation late on Saturday and that the Department of Homeland Security (DHS) and the FBI were notified. In 2016, Kemp alleged that a federal agency had tried to breach the state's voter system.
"While we cannot comment on the specifics of an ongoing investigation, I can confirm that the Democratic Party of Georgia is under investigation for possible cyber crimes," said Candice Broce, spokeswoman for Kemp's office.
A DHS official said in an email that the department was aware of the latest allegation. The official declined to say if the agency was investigating.
The Federal Bureau of Investigation declined to comment.
Democrats, who have accused Kemp of using Georgia's strict voter identification laws to suppress the vote among minorities, said his office had no basis for opening the probe.
"Brian Kemp's scurrilous claims are 100 percent false," Rebecca DeHart, executive director of the Georgia Democratic Party, said on Sunday. "This political stunt from Kemp just days before the election is yet another example of why he cannot be trusted and should not be overseeing an election in which he is also a candidate."
On Friday, two federal courts issued separate rulings requiring Kemp's office to allow thousands of naturalized U.S. citizens to vote after their registrations were put on hold and to retain some absentee ballots with potential signature mismatches.
Former U.S. President Jimmy Carter, a Democrat and former Georgia governor, has called on Kemp to step down from the secretary of state position because of what Carter said was a conflict of interest.
A wave of robocalls using racist language went out in Georgia in recent days apparently aimed at hurting the Abrams campaign. Both Abrams and Kemp denounced the calls.
During the last year of the Obama administration, Kemp said a DHS computer made an unsuccessful attempt to breach the firewall guarding Georgia's voter data. He complained on his Facebook page at the time that the agency had "been less than forthcoming" in responding to his allegation.
The DHS inspector general in June 2017 said Kemp's complaint was without merit.
Kemp's latest claims were met with skepticism from cyber security experts, who noted that the process of identifying who is behind a particular hack is lengthy, time-consuming and extremely difficult.
"Does the Georgia Secretary of State have the forensics capability and expertise necessary to investigate their own potential breach?" Alex Stamos, Facebook's former security chief, asked on Twitter.
The FBI's election security task force and the Justice Department's computer crimes unit are best positioned to investigate any hack, Stamos added.
For all Reuters election coverage, click: https://www.reuters.com/politics/election2018
(Reporting by Joseph Ax and Jim Finklein New York; Additional reporting by Christopher Bing; Editing by Scott Malone and Paul Simao)