Lt. Gov. Ken Ard said in a letter Friday to Senate leaders and the governor that he was sorry and it was his responsibility to make sure the money was spent correctly.
A grand jury began investigating the 48-year-old Republican in July. Ard has already paid a $48,000 ethics fine for using money from his 2010 campaign to pay for personal items, like clothes, football tickets and a flat-screen TV.
The lieutenant governor is paid $46,545 for the part-time job that includes presiding over the state Senate.
By state law, the Senate President Pro Tem will become lieutenant governor.