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

A spokeswoman for Sen. Bernie SandersBernie SandersSanders joins Biden atop 2020 Democratic field: poll The Hill's Morning Report - Trump trial begins with clashes, concessions Trump on Clinton's Sanders comments: 'She's the one that people don't like' 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 BidenSanders joins Biden atop 2020 Democratic field: poll The Hill's Morning Report - Trump trial begins with clashes, concessions Trump says impeachment lawyers were 'really good' 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 HarrisRep. Bobby Rush endorses Bloomberg's White House bid Actor Michael Douglas endorses Bloomberg for president Democrats: McConnell impeachment trial rules a 'cover-up,' 'national disgrace' 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 WarrenSanders joins Biden atop 2020 Democratic field: poll The Hill's Morning Report - Trump trial begins with clashes, concessions Hillary Clinton tears open wound with her attack on Sanders MORE (D-Mass.). Those three candidates have been leading most recent national polls, along with surveys in Iowa and New Hampshire.  

—Tess Bonn