League of Women Voters believes NC Democrats are entitled under the Constitution to more early voting when dozens of states have zero early voting

North Carolina is sued by the League of Women Voters, the ACLU and minority groups for simply reducing the days, not necessarily the hours of early voting.  Interesting enough, according a survey of states by the NCSL, there are at least a dozen states that do not include even one day of early voting and states that do not provide for absentee voting unless there is a valid excuse. 

Are all these states violating the constitutional rights of voters to have early voting?  Do voters have a absolute right to three weeks of early voting versus two weeks of early voting.  Early voting is a recent new way of voting and less than a decade ago, there was no early voting anywhere in the country.

The complaint is here.

Update:  Early Voting has not been widespread in the United States but in 1992 about 7% of votes were early votes.  By 2000, that had risen to 16%.  Early Voting is a more form of voting in the last two decades.  Time flies.