Conservative groups are pushing to clean voter rolls. Others see an effort to sow election distrust

Conservative groups are systematically attempting to challenge the legitimacy of large numbers of voter registrations across the country before the presidential election.

The strategy is part of a wider effort raising questions about the integrity of this year's election as former President Donald Trump repeatedly claims without evidence that his opponents are trying to cheat.

The voter roll tactics include mass door-knocking campaigns, using special software designed to identify voters whose eligibility could be challenged and a crush of lawsuits. Some of those have been brought by the Republican National Committee, which hosts the GOP's national convention this coming week.

Several Republican secretaries of state are combing through voter lists on their own, including in Ohio and Tennessee, or to comply with aggressive new state voting laws.