All over America GOP controlled legislatures have been enacting laws to restrict the ability of citizens to vote. There are ID requirements, proof of residency requirements, narrowing of voting hours and days etc. etc
The powers that run the GOP have realized that they have little support beyond the white middle and upper classes so they want as few people as possible to vote. They're also working on gerrymandering schemes that will minimize the influence of the "outgroups".
The Rs who control the NH legislature were faced with a difficult job since the state is almost entirely white and middle class, yet it has been trending blue for over a decade. They identified the one group that is consistently blue but not especially prone to voting, college students 18 and over. So they passed a bunch of laws concerning registration, residency, documentation and the like.
The New Hampshire Supreme Court has ruled unanimously (4-0) that they're all unconstitutional!
How cool is that!