Here are some of the internals:
UNH surveyed 538 randomly selected New Hampshire adults by land line and cell phone between April 9 and 20. The poll has a margin of error of 4.2 percent.
Among those polled, 486 participated in the head-to-head match up question. Of those, 205 said they were registered undeclared voters, 137 said they were registered Democrats and 112 said they were registered Republicans. A total of 215 of those polled identified themselves as Democrats, 183 identified themselves as Republicans and 78 identified themselves as independents.
Random selection is not scientific and a poor indicator. Samples should be based upon current party affiliation numbers plus likely voters.
“A total of 215 of those polled identified themselves as Democrats, 183 identified themselves as Republicans and 78 identified themselves as independents.”
So 17% more Dems were polled than Republicans. Gallup must be using BLS statisticians.