Michelle Obama would be tied with Biden as frontrunner if she ran in 2020, poll shows

Former first lady Michelle ObamaMichelle LeVaughn Robinson ObamaTrump: House Judiciary should investigate Obama Netflix deal instead of his business 2020 is not a family affair, for a change Former speechwriter says Michelle Obama came up with 'when they go low we go high' line MORE tied with former Vice President Joe BidenJoe BidenSanders supporters cry foul over Working Families endorsement of Warren California poll: Biden, Sanders lead Democratic field; Harris takes fifth Poll: Biden holds five-point lead over Warren among New York Democrats MORE as the top choice among Democratic voters when asked who should be the party's nominee in 2020.

A Hill-HarrisX poll released Tuesday found that 25 percent of Democrats said they would back Obama in the party primary over nine other declared or potential candidates, including Sens. Bernie SandersBernie SandersSanders supporters cry foul over Working Families endorsement of Warren California poll: Biden, Sanders lead Democratic field; Harris takes fifth Kamala Harris calls for new investigation into Kavanaugh allegations MORE (I-Vt.), Kamala HarrisKamala Devi HarrisCalifornia poll: Biden, Sanders lead Democratic field; Harris takes fifth Kamala Harris calls for new investigation into Kavanaugh allegations Poll: Biden holds five-point lead over Warren among New York Democrats MORE (D-Calif.), Elizabeth WarrenElizabeth Ann WarrenSanders supporters cry foul over Working Families endorsement of Warren California poll: Biden, Sanders lead Democratic field; Harris takes fifth Kamala Harris calls for new investigation into Kavanaugh allegations MORE (D-Mass.), and former Rep. Beto O’Rourke (D-Texas).

Obama has said she is not running, and Biden has not announced whether he will launch another White House bid.

Harris came in third among Democratic voters, with 12 percent saying they would support her. Sanders was a close fourth, at 11 percent. O’Rourke, former New York City Mayor Michael Bloomberg, Warren, and Sens. Cory BookerCory Anthony BookerOvernight Energy: Top presidential candidates to skip second climate forum | Group sues for info on 'attempts to politicize' NOAA | Trump allows use of oil reserve after Saudi attacks Poll: 33 percent of voters undecided on who won third Democratic debate Jon Bon Jovi: Booker would 'do an amazing job' as president MORE (D-N.J.), Amy KlobucharAmy Jean KlobucharObama, Bush among those paying tribute to Cokie Roberts: 'A trailblazing figure' Kamala Harris calls for new investigation into Kavanaugh allegations Overnight Energy: Top presidential candidates to skip second climate forum | Group sues for info on 'attempts to politicize' NOAA | Trump allows use of oil reserve after Saudi attacks MORE (D-Minn.) and Sherrod BrownSherrod Campbell BrownHillicon Valley: Google to promote original reporting | Senators demand answers from Amazon on worker treatment | Lawmakers weigh response to ransomware attacks Senate Democrats want answers on 'dangerous' Amazon delivery system Hillicon Valley: Uber vows to defy California labor bill | Facebook, Google, Twitter to testify on mass shootings | Facebook's Libra to pursue Swiss payments license MORE (D-Ohio) all failed to exceed 6 percent.

Biden and Obama garnered 23 percent and 22 percent, respectively, when factoring in independent voters, who are allowed to vote in many state primary elections.

When combining Democratic and independent voters, Sanders received 12 percent, followed by 8 percent for Harris.

Molly Murphy, a partner at Democratic consulting firm ALG Research, said Obama's popularity is helped in large part because she has never thrown her hat into the ring.

"Because she's never been a candidate, she's never been on the ballot, she's avoided a certain degree of scrutiny that candidates face. And so she's all icing for people, it's all good," Murphy said Tuesday on "What America's Thinking," Hill.TV's show about public opinion and polling.

In the Hill-HarrisX poll, 12 percent of independents and Democrats combined said they preferred another candidate, beyond the choices that were offered, suggesting some dissatisfaction among non-Republican voters with the field of declared and potential candidates.

A November Hill-HarrisX poll found that 14 percent of Democratic respondents picked "none of the above" when asked to choose between Warren, Biden, Sanders, Booker, Harris, Bloomberg and former Democratic presidential nominee Hillary ClintonHillary Diane Rodham ClintonSanders supporters cry foul over Working Families endorsement of Warren The Hill's 12:30 Report: Trump heads to California Hillary Clinton: Voter suppression has led to 'crisis in democracy' in the US MORE.

Obama's surprise appearance at the Grammy awards this month promoted some speculation about a possible 2020 bid. In December, the former first lady said that she had "never" considered a political career and that she had no intention of running for office.

The Hill-HarrisX survey was conducted Feb. 17-18 among a nationally representative sample of registered voters. The overall survey has a sampling margin of error of 3 percentage points.

The group of Democratic respondents has a sampling margin of error of 5 percentage points, and the Democratic and independent set has a sampling margin of error of 4 percentage points.

—Matthew Sheffield