Five voters in three Georgia counties filed an emergency lawsuit late Tuesday in federal court in Atlanta asking a judge to bar Secretary of State Brian Kemp from continuing to use the powers of his office to influence the 2018 general election.

Kemp, the Republican candidate for governor, has ignored repeated calls from Democrats and voting rights organizations to step down as the state’s chief election officer while he campaigns for the state’s highest office. Those calls intensified this week after Kemp announced he had launched a criminal investigation of the state Democratic Party in connection with information shared with his outside counsel, warning that the state voter registration web page was vulnerable to hackers.