SEATTLE — More than half of states are now working in broad alliances to scrub voter rolls of millions of questionable registrations, identifying people registered in multiple states and tens of thousands of dead voters on election lists.
Poll managers, who are looking for more states to get involved, say the efforts are necessary because outdated voter registration systems are unable to keep up with a society in which people move frequently. While many of the registration problems are innocent, some officials fear the disorder in the system invites trouble.
‘‘It creates an environment where there could be more problems,’’ said Scott Gessler, Colorado’s secretary of state. ‘‘It’s a precursor to potential fraud, no doubt about it.’’
Half of all states have now joined a consortium anchored by the state of Kansas, compiling their voter registration lists at the end of every year to assess for duplicates. That program has grown rapidly since beginning in 2005.
Meanwhile, seven states are coordinating on another project that makes those assessments more frequently with advanced algorithms, while also checking for deceased voters.
The efforts are already finding massive numbers of outdated or problematic registrations. This year, the Kansas project identified some 5 million records that were questionable in 22 states and identified some people who voted in multiple states.
The newer project identified hundreds of thousands of other registrations that need updating, including 23,000 people who were dead.
Both data-matching programs are bipartisan. That’s different than just before the 2012 election, when Republicans predominantly led efforts they portrayed as issues of election integrity, including the purge of possible noncitizens from rolls and the passage of voter ID laws. Democrats and voter advocacy groups had raised concerns about those efforts, fearing they could prevent legitimate voters from casting a ballot.