When voters go to the polls they may see members of an advocacy coalition trying to gauge the effects of North Carolina's new elections law.
Tuesday's primary is the first election since the law took effect.
Several provisions are being challenged in at least four federal and state lawsuits, but the law remains fully in force.
The law reduced the number of days of in-person early voting and ended same-day registration during that early period. It also requires people to show photo identification to vote in person beginning in 2016.
Two voter advocacy groups have teamed up to train over 400 volunteers to monitor precincts.
Bryan Perlmutter, a spokesman for one of the groups, says the volunteers will provide information about how the new law is being implemented.