It depends how you want that measured. And that's why you are seeing different answers because of the confusion. In the north-south distance, can islands be included? (The n-s measurement of a surprising number of states will depend on that specification.).
You would need to specify such things as:
Does the line have to be across land entirely within the state?
Can the line cross into another state or international water, or must it be entirely on contiguous land within the state?
Or do you simply want to compare latitude numbers?
As you probably know, a state's "longest" measurement is not always north-south. The longest dimension of a state can be in any directional orientation. To compare the longest states, we must measure from one extreme point on a border to the extreme other point farthest away. The longest states are:
1) Hawaii (based on the distance from South Point, Hawaii Island to Kure island)
2) Alaska
3) California
4) Texas
Maine
The state with the longest Atlantic coastline is Florida at 1350 miles, or 2170 kilometers. It is also the second longest coastline in the US after Alaska.
The Second longest shoreline is California The Second longest is Michigan. 1st is Alaska with over 6,000 miles, Michigan is 2nd with over 3,000 miles and California has around 1,000 miles.
The state with the longest coastline in the US is Alaska.
Michigan
Florida
Alaska is the US state which shares the longest border with Canada.
In terms of length, the current longest country constitution is India's (117,000+ words). For other entities, the current length champion is US State of Alabama, at 357,000+ words. The US State of California has the second longest, world-wide.
Mississippi
The Misissippi
Mississippi
The Misissippi