RNA - The Emerson College poll published on Tuesday found that Biden enjoys the support of 25 percent of registered voters after a 6-point fall from the same poll in August, while Senator Elizabeth Warren (D-Mass.) has surged to 23 percent, an 8-point rise since last month’s survey.
Senator Bernie Sanders (I-Vt.) ranked third with 22 percent, a 2-point drop from August.
Entrepreneur Andrew Yang came in at fourth place at 8 percent, beating out South Bend, Indiana, Mayor Pete Buttigieg with 6 percent and Senator Kamala Harris (D-Calif.) at 4 percent.
The poll also found that Biden is supported by 42 percent of voters aged 50 or older, while Sanders is regarded favorite for 28 percent of voters under 50 and Warren has 23 percent support from each group.
The Emerson College poll was conducted between September 21 and 23 among 1,019 registered voters with a margin of error of 3 percentage points.
Biden is the front-runner for the Democratic presidential nomination for the 2020 election.
Biden has come under fire for his clanger-laden campaigns during his latest presidential run and his slip-ups have been providing US President Donald Trump with ammunition to attack Democrats.
Since launching his bid for 2020 presidency, the veteran politician has been referred to as "Sleepy Joe" by Trump, among other cases of name-calling.
The 76-year-old has also been lambasted for what his opponents and others have deemed inappropriate touching, hugging and sniffing of women and children. Biden has dismissed such allegations.