Updated 7:34 p.m. Eastern Time
Two government officials tell CBS News that Republican presidential candidate Herman Cain has been approved for Secret Service protection.
The Secret Service would not say why the decision was made. Cain has received threats as far back as when he was CEO of Godfather's Pizza.
The Cain campaign would not confirm that Cain had been approved for Secret Service protection.
The news comes after the Cain campaign apologized after a. The Cain campaign said after the incident that it was "reviewing our own internal security procedures."
Then-Sen. Barack Obama received Secret Service protection on May 3, 2007. Then-Sen. Hillary Clinton, who also sought the presidency in the 2008 cycle, already had Secret Service protection because he husband had recently been president; her official campaign protection began on November 29, 2007.
Among the candidates who have gotten Secret Secret protection are Rev. Jesse Jackson (starting November 23, 1987 and November 10, 1983), Pat Robertson (December 1, 1987) and Sen. Edward Kennedy (October 25,1979). Six candidates received Secret Service protection in the 1976 campaign cycle.
Congress authorized protection for major presidential candidates after Robert Kennedy was assassinated in 1968, as he was seeking the presidency. A congressional panel signs off on all requests for Secret Service protection.