WASHINGTON (AP) — Republican Rep. Darrell Issa of California says he will not seek re-election after serving out his ninth term in Congress.

Issa's decision continues a string of GOP lawmakers who have decided to retire rather than take on what would be a difficult re-election battle.

Democrats had made defeating Issa one of their top priorities in the midterm elections.

Issa is a longtime nemesis of the Democrats and then-President Barack Obama. He once served as chairman of the House Oversight and Government Reform Committee and led investigations of the IRS and its treatment of conservative groups and Benghazi.