Even though Vice President Joe Biden hasn't yet entered the 2016 presidential race, a new poll released Wednesday shows he has surpassed Bernie Sanders and is now within 8 percentage points of Democratic front-runner Hillary Clinton.

Clinton still holds the top spot in Bloomberg's national poll, with the support of 33 percent of registered Democrats. But Biden, still mulling over whether to enter the race, now comes in second with 25 percent. Sen. Bernie Sanders, I-Vt., who has positioned himself as Clinton's most progressive rival and surged ahead in polls in early-voting states, follows close behind with 24 percent.

Former Virginia Sen. Jim Webb got 2 percent and former Maryland Gov. Martin O'Malley 1 percent.

Forty-seven percent of respondents said they think Biden should enter the race, compared to 37 percent who said he should stay out, and 15 percent who were unsure.

The vice president lost his son Beau to brain cancer earlier this year and has said he is not sure whether he is emotionally prepared to run another presidential campaign and be there for his family at the same time, as HNGN reported.

Clinton was once the dominant favorite among Democrats, but the controversy surrounding her use of a private email system during her time as Secretary of State has led to a drastic decline in her polling position, as well as favorability ratings.

Only 38 percent viewed her favorably in Bloomberg's poll, compared to 54 percent who viewed her unfavorably. Biden came in with a 49 percent/41 percent favorable/unfavorable split.

Among Democrats and Democratic-leaners, Biden led by far in terms of favorability, with 80 percent saying they hold a favorable view of him, compared to 14 percent who have an unfavorable view. Seventy percent viewed Clinton favorably and 25 percent viewed her unfavorably, and Sanders came in with a 56 percent/9 percent favorable/unfavorable split.

The poll surveyed 1,001 adults between Sept. 18-21, and has a margin of error of 3.1 percentage points. Questions asked only to the 375 Democrats and Democratic leaners have a margin of error of plus or minus 5.1 percentage points.