Biden, Warren, Sanders stay on top; health is now an issue for Sanders: POLL - ABC News
Florida primary: Poll shows Biden leads Sanders, except with young
Biden, Sanders other Democrats lead Trump in Michigan, poll finds
Biden, Sanders both top Trump in general election: poll | The Hill
Biden, Sanders Are Running Neck and Neck in Nationwide Poll - Bloomberg
Iowa Poll: Biden and Sanders Top List of Favored 2020 Democrats
2020 Poll: Biden, Sanders Lead Democratic Race To Take On Trump For President : NPR
National poll: Biden, Warren and Sanders locked together at top of primary - POLITICO
New poll shows Joe Biden ahead of Bernie Sanders in Missouri presidential primary | FOX 4 Kansas City WDAF-TV | News, Weather, Sports
Sanders, Biden are neck-and-neck in new NBC/WSJ national poll
Bernie Sanders surges to join Biden atop Democratic presidential pack in new poll | CNN Politics
Feb. 27, 2020 Press Release | Department of Political Science | UMass Amherst
Elizabeth Warren and Joe Biden drop in new 2020 poll - Los Angeles Times
Poll: Joe Biden, Bernie Sanders in dead heat with Texas Democratic primary voters
Suffolk/Globe poll finds Sanders, Warren, Buttigieg, Biden in tight race in N.H. - The Boston Globe
Bernie Sanders Pulls Away From Pack in California | KQED
Chart: Bernie Sanders Takes the Lead | Statista
/cdn.vox-cdn.com/uploads/chorus_asset/file/19753741/1208692873.jpg.jpg "Bernie Sanders leads Joe Biden in national ranked-choice poll — but it's close - Vox")
Bernie Sanders leads Joe Biden in national ranked-choice poll — but it's close - Vox
NBC News poll: Biden holds narrow lead over Sanders in South Carolina
CNN Poll of Polls: Biden and Sanders lead national Democratic primary | CNN Politics
Bernie Sanders is now tied with Joe Biden Reuters poll
USC Dornsife/LA Times poll: Biden is the favorite among likely voters at nearly 2:1 - Press Room USC
Bernie Sanders, Joe Biden, Elizabeth Warren lead new California poll
