Democrats are most confident that former Vice President Joe Biden Joe BidenOmar fires back at Trump over rally remarks: 'This is my country' Trump mocks Biden appearance, mask use ahead of first debate Trump attacks Omar for criticizing US: 'How did you do where you came from?' MORE and Sen. Bernie Sanders Bernie SandersButtigieg stands in as Pence for Harris's debate practice Bernie Sanders warns of 'nightmare scenario' if Trump refuses election results Harris joins women's voter mobilization event also featuring Pelosi, Gloria Steinem, Jane Fonda MORE (I-Vt.) can defeat President Trump Donald John TrumpOmar fires back at Trump over rally remarks: 'This is my country' Pelosi: Trump hurrying to fill SCOTUS seat so he can repeal ObamaCare Trump mocks Biden appearance, mask use ahead of first debate MORE in a general election, according to a new Hill-HarrisX poll.

In the survey, 75 percent of Democratic respondents said that they believed that Biden had a strong or some chance of beating Trump in the general election next year, while 64 percent said the same of Sanders.

None of the other potential and declared Democratic candidates were rated by more than half of the party's voters as having at least some chance of defeating Trump.

Forty-five percent of Democrats in the survey said that they believed former Rep. Beto O'Rourke Beto O'RourkeJimmy Carter says his son smoked pot with Willie Nelson on White House roof O'Rourke endorses Kennedy for Senate: 'A champion for the values we're most proud of' 2020 Democrats do convention Zoom call MORE (D-Texas) had at least some chance of defeating the president, while 43 percent said the same about Sen. Kamala Harris Kamala HarrisButtigieg stands in as Pence for Harris's debate practice First presidential debate to cover coronavirus, Supreme Court Harris joins women's voter mobilization event also featuring Pelosi, Gloria Steinem, Jane Fonda MORE (D-Calif.).

Forty-two percent of Democrats said that Sen. Elizabeth Warren Elizabeth WarrenHarris joins women's voter mobilization event also featuring Pelosi, Gloria Steinem, Jane Fonda Judd Gregg: The Kamala threat — the Californiaization of America GOP set to release controversial Biden report MORE (D-Mass.) had at least some chance of victory, while only 36 percent said they believed Sen. Cory Booker Cory Anthony BookerBipartisan praise pours in after Ginsburg's death DHS opens probe into allegations at Georgia ICE facility Democratic lawmakers call for an investigation into allegations of medical neglect at Georgia ICE facility MORE (D-N.J.) had at least some chance of beating Trump, and just 25 percent said the same about Sen. Amy Klobuchar Amy KlobucharSocial media platforms put muscle into National Voter Registration Day Battle lines drawn on precedent in Supreme Court fight Sunday shows - Ruth Bader Ginsburg's death dominates MORE (D-Minn.). Seventeen percent said they believed entrepreneur Andrew Yang Andrew YangDoctor who allegedly assaulted Evelyn Yang arrested on federal charges The Hill's Campaign Report: Biden weighs in on police shootings | Who's moderating the debates | Trump trails in post-convention polls Buttigieg launches his own podcast MORE had at least some chance.

Biden, who is expected to soon enter the Democratic race, and Sanders have routinely polled at the top of surveys of Democratic voters. The Hill-HarrisX survey suggests Dems desperate to eject Trump from the White House may be gravitating to the two men because they see them as having the best chances to defeat Trump, according to Sophia Tesfaye, the deputy politics editor at Salon.com.

"This time around, especially after 2016 for Democrats, the biggest driver for popularity is can you beat Donald Trump," she said Tuesday on "What America's Thinking."

Both Biden and Sanders are making plays to appeal to white, working-class voters in states such as Pennsylvania, Michigan and Ohio that Trump won in 2016.

The poll found that 49 percent of Democrats said Biden had a strong chance of winning while 26 percent said he had some chance. Only 10 percent said they believed that Biden had a small chance of winning while just 5 percent said he had almost no chance. Fifteen percent said they were unsure.

Thirty-one percent of Democrats said Sanders had a strong chance of victory while 33 percent said he had some chance of winning. Eighteen percent said that Sanders had only a small chance of beating the president while 7 percent said they believed he had almost no chance. Twelve percent were unsure.

Republicans polled thought that all of the Democratic hopefuls would fall to Trump, but Biden is seen as the greatest threat.

Thirty-two percent said Biden had at least some chance of victory, compared to 28 percent for Sanders. Just 17 percent said O'Rourke had at least some chance of victory while 16 percent said Booker had some chance. All the other aspirants were rated as having lower odds by GOP voters.

Independents were also more skeptical of the Democratic candidates' chances. Forty-one percent said they believed Biden had at least some chance of willing while 39 percent said that Sanders did.

Twenty-seven percent of respondents who identified as independents said that O'Rourke had at least some chance of victory while 24 percent said the same about Harris. Nineteen percent of independents said that Warren had at least some chance and 18 percent said Booker had a chance to win. The other candidates trailed with less than 15 percent of independents saying they had at least some chance.

Overall, 50 percent of registered voters of all stripes said that Biden had at least some chance compared to 44 percent for Sanders, 30 percent of O'Rourke, 28 percent for Harris, and 26 percent for Warren. Twenty-four percent said Booker had at least some chance.

"For candidates that have very high name recognition, like Elizabeth Warren, Joe Biden, or Bernie Sanders, this is not good news," Dritan Nesho, the CEO of HarrisX said.

"I think the other candidates that have a lot of room to grow will see their numbers shift up and it seems to me that that's where the problem is and the traction might be in the future months," Nesho added.

Across age groups and among voters of all partisan persuasions, Biden was the Democratic hopeful that voters said had the best odds with around 50 percent saying he had at least some chance of victory. But among younger voters — those between 18 and 34 years of age — 53 percent said they believed that Sanders could defeat Trump. Assessments of the senator's chances were lower among voters 35 and up.

A Hill-HarrisX survey released Monday found that 28 percent of Democratic and independent voters said they supported Biden to become the Democratic presidential nominee, 20 percent backed Sanders, 8 percent backed O'Rourke and Warren, and 6 percent preferred Booker.

—Matthew Sheffield