The NBC News / Wall Street Journal / Marist Poll was done on February 2nd and 3rd of a random sample of 567 likely New Hampshire Democratic voters, and has a margin of error of 4.1 points.
The Boston Globe / Suffolk University Poll was done between February 2nd and 4th of a random sample of 500 likely New Hampshire Democratic voters. No margin of error was given.
The two give a very different picture -- with one saying there's a 20 point gap, and the other saying the gap is only 9 points.
