Hillary Clinton still leads Democratic primary field, but doesn't have the biggest lead over Donald Trump. Bernie Sanders beats Trump by 7 points in a new hypothetical matchup.

Clinton still holds a substantial lead over Vermont Sen. Bernie Sanders 43-25, followed by unannounced candidate Vice President Joe Biden, with Martin O'Malley, Lincoln Chaffee and Lawrence Lessig trailing. Among Democrats, only 11 percent say that they "would definitely not support" the former secretary of state during her bid for the White House, according to a Thursday Quinnipiac poll.

When matched up against Republicans, Clinton finds herself in nearly a dead tie with GOP leading lady Carly Fiorina. Clinton trails her 43-44. Clinton is behind Ben Carson 49-42 and Jeb Bush 44-42, but leads Republican front-runner Donald Trump 45-43.

Sanders leads 49-42. He also nearly ties Fiorina, trailing her 44-43, ties Bush 44-44 and trails Carson 49-39. The Democratic challenger is viewed less unfavorably than Clinton, with only 28 percent of Democrats viewing him negatively, whereas Clinton had a 55 percent unfavorable rating.

Sanders has built a significant lead over Clinton in New Hampshire, while the polling in Iowa has shown conflicting results.

As the former secretary of state's private email scandal unfolds, her trustworthiness rating has also plummeted. Sixty-eight percent of independent voters, a key bloc in the general election, find Clinton to be untrustworthy.