In what he called an effort to restore integrity to the office, state Sen. Nathan Johnson on Tuesday launched a campaign to replace Ken Paxton as Texas attorney general. “It is significant that Ken Paxton has abused the office,

Republican Ken Paxton is challenging U.S. Sen. John Cornyn instead of seeking another term as Texas attorney general.

The third-term lawmaker enters into the crowded GOP contest as the first, and only, heavyweight Democratic contender. If he's able to clinch the Democratic primary, Johnson may go up against one of his colleagues,