Kast took the position after the 2000 election debacle when President Bush won the state and the presidency by only 537 votes. A recount was halted by the Supreme Court, effectively giving the election to Bush.
Kast's resignation comes as scrutiny of the 2004 election process intensifies.
One issue is a list of 48,000 names identified as possible felons ineligible vote. Some county elections officers and many other critics question the accuracy of the list.