The 79-year-old Republican, who is under fire from the Justice Department over the alleged racial profiling of Hispanics and has a national reputation for his hard-line stance on illegal immigrants, announced plans to run for re-election Friday.
"It is an honor and a privilege to serve as sheriff of Maricopa County. I am running for a sixth term and will continue to protect the citizens of Maricopa County by enforcing all the laws," the Los Angeles Times quoted Arpaio as saying.
The Justice Department has accused Arpaio of fostering discrimination against Latino residents through the sheriff's immigration-enforcement efforts and treatment of Hispanic inmates in Maricopa County jails.
The Phoenix Business Journal said Arpaio has $6 million in his campaign coffers and strong support among conservatives and older voters.