WASHINGTON — Field workers for President Obama’s campaign fanned out across the country over the weekend in an effort to confront a barrage of new voter identification laws that strategists say threaten the campaign’s hopes for registering new voters ahead of the November election.

In Wisconsin, where a new state law requires those registering voters to be deputized in whichever of the state’s 1,800 municipalities they are assigned to, the campaign sent a team of trainers armed with instructions for complying with the new regulations.

In Florida, the campaign’s voter registration aides traveled across the state to train volunteers on a new requirement that voter registration signatures be handed in to state officials within 48 hours after they are collected.

And in Ohio, Mr. Obama’s staff members have begun reaching out to let voters know about new laws that discourage precinct workers from telling voters where to go if they show up at the wrong precinct.