PPP poll finds eight Republicans beating her in head-to-head contests in the swing state.
A majority also think the private email server endangered national security.
Walker, who led for months, is on the decline, with Carson surging to second.
Julian Hattem 07/27/15 09:18 AM EDT
Most voters support the Iran deal, according to the poll.
A poll finds Trump would siphon significant support from Bush in a three-way race with Clinton.
Her unfavorable rating has jumped 8 points since she announced her White House bid.
Survey also shows Biden could be a strong Democratic challenger.
The poll finds Hassan up 45-44 in a hypothetical 2016 Senate matchup.
Trump was the preferred GOP presidential nominee for 15 percent of respondents.
Christie's job approval rating at home has been trending downward for months.