Bernie Sanders Campaign Rally In Denver On Feb. 16, 2020
/ CBS News
Democratic presidential candidate Vermont Senator Bernie Sanders addresses supporters during a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders addresses supporters during a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders addresses supporters during a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders (L) and his wife, Jane Sanders, wave to supporters at the end of a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders greets supporters after a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Supporters of Democratic presidential candidate Vermont Senator Bernie Sanders cheer during his campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Supporters of Democratic presidential candidate Vermont Senator Bernie Sanders cheer during his campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders addresses supporters during a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders (R) and his wife, Jane Sanders, greet supporters at the start of a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Supporters of Democratic presidential candidate Vermont Senator Bernie Sanders cheer during his campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders addresses supporters during a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders greets supporters after a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders addresses supporters during a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders addresses supporters during a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders addresses supporters during a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders addresses supporters during a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
Democratic presidential candidate Vermont Senator Bernie Sanders walks onto the stage at the beginning of a campaign rally in Denver on Feb. 16, 2020. (credit: JASON CONNOLLY/AFP via Getty Images)
Bernie Sanders Rallies Voters In Denver Before Super Tuesday
A young supporter holds up a sign for Democratic presidential candidate Sen. Bernie Sanders as he speaks to a large crowd of supporters at a rally in the Colorado Convention Center on February 16, 2020 in Denver. (Photo by Marc Piscotty/Getty Images)