DES MOINES, Iowa (AP) — A former Iowa assistant attorney general plans to challenge the Republican state auditor in next year's midterm elections.

Rob Sand, a Democrat who served with Attorney General Tom Miller between 2010 and earlier this year, announced his candidacy for state auditor Monday against incumbent Mary Mosiman.

Sand gained attention in the AG's office for prosecuting a jackpot scandal that involved a former lottery programmer admitting to rigging computers that enabled him to pick winning numbers in several lottery games. Sand also prosecuted fraud related to the state's filmmaking tax credit program.

Mosiman was appointed state auditor in 2013 following the resignation of former State Auditor David Vaudt. She was elected to a full four-year term the following year.