Voting rights activists worried this year could bring a tsunami of new voting restrictions. It’s arrived. As of last month, Republican lawmakers in 43 states had introduced more than 250 bills that would make it more difficult to vote, according to the Brennan Center for Justice at the New York University Law School, up from about 100 in 28 states two months ago. But Democrats also are focusing on ballot access during this year’s legislative sessions: They have introduced nearly three times as many bills that would make it easier to vote. Despite the logistical success of the November presiden…