The poll found Shaheen leading Brown 47 percent to 35 percent among registered voters with 13 percent undecided. Brown, the former Massachusetts senator who's now running for the U.S. Senate in New Hampshire, is widely regarded as the likely Republican nominee to face Shaheen.
But in a hypothetical matchup against former Sen. Bob Smith (R), Shaheen's lead is essentially the same. The Vox Populi poll found Shaheen leading Smith 45 percent to 34 percent.
That's despite the fact that, according to the poll, Brown is the favorite to win the nomination. Thirty-eight percent said they would vote for Brown in the GOP New Hampshire Senate primary while just 13 percent said they would vote for Smith.
The poll was conducted May 14 to 15 among 707 registered voters. It had a margin of error of plus or minus 3.6 percentage points. The margin of error for primary voters was plus or minus 5.2 percentage points.