Sanders spokeswoman: A lot of candidates will have to answer for their past

A spokeswoman for Sen. Bernie SandersBernie SandersOvernight Health Care — Presented by Partnership for America's Health Care Future — Pelosi unveils signature plan to lower drug prices | Trump says it's 'great to see' plan | Progressives pushing for changes Krystal Ball calls on Sanders to follow Yang's lead on war on drugs Buttigieg calls Warren 'evasive' on Medicare for all MORE (I-Vt.) on Thursday said that many of the progressive senator’s fellow 2020 contenders will have to answer for their past stances on various issues.

“A lot of candidates are going to have to answer for their histories — both in office and before they joined political office,” Briahna Joy Gray, told Hill.TV.

Gray did not mentions any candidates by name, but said she's not worried about Sanders, saying his “longevity is a selling point instead of something that you have to excuse.”

“We have a candidate who has been in office so, so long and yet at the same time doesn’t have all of those foibles,” she told Hill.TV, citing his long-standing support of civil rights.

Sanders is behind in the polls to former Vice President Joe BidenJoe BidenGiuliani clashes with CNN's Cuomo, calls him a 'sellout' and the 'enemy' Giuliani says 'of course' he asked Ukraine to look into Biden seconds after denying it Trump whistleblower complaint involves Ukraine: report MORE, whose past stance on the Iraq War and the 1994 crime bill have both come under attention. Biden also took criticism from Sen. Kamala HarrisKamala Devi HarrisTwo former Congressional Black Caucus chairmen back Biden Strippers, 'Hustlers' and the Democratic debates 2020 Dems honor Emily Clyburn MORE (D-Calif.), another presidential hopeful, during the first presidential debate for his past opposition to federal busing of students.  

Sanders will take the debate stage tonight in Houston at Texas Southern University alongside Biden and fellow progressive Sen. Elizabeth WarrenElizabeth Ann WarrenOvernight Health Care — Presented by Partnership for America's Health Care Future — Pelosi unveils signature plan to lower drug prices | Trump says it's 'great to see' plan | Progressives pushing for changes Buttigieg calls Warren 'evasive' on Medicare for all Sanders hits 1 million donors MORE (D-Mass.). Those three candidates have been leading most recent national polls, along with surveys in Iowa and New Hampshire.  

—Tess Bonn