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Democratic presidential hopefuls US Senator for New York Kirsten Gillibrand (L) and US Senator for Colorado Michael Bennet (R) speak in the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019. SAUL LOEB/AFP/Getty Images

Democratic presidential hopefuls Former Vice President Joseph R. Biden (L) and US Senator for Vermont Bernie Sanders (R) speak in the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019. SAUL LOEB/AFP/Getty Images

Democratic presidential hopeful US Senator for New York Kirsten Gillibrand speaks during the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019. SAUL LOEB/AFP/Getty Images

Democratic presidential hopeful Mayor of South Bend, Indiana Pete Buttigieg speaks during the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019. SAUL LOEB/AFP/Getty Images

Democratic presidential hopeful former US Representative for California's 15th congressional district Eric Swalwell speaks during the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019. SAUL LOEB/AFP/Getty Images

Democratic presidential hopeful US author Marianne Williamson speaks during the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019. SAUL LOEB/AFP/Getty Images

Democratic presidential candidate Sen. Kristen Gillibrand, D-N.Y., left, speaks during the Democratic primary debate hosted by NBC News at the Adrienne Arsht Center for the Performing Arts, Thursday, June 27, 2019, in Miami, as former Colorado Sen. Michael Bennet listens.

Democratic presidential hopeful US Senator for Vermont Bernie Sanders (L) and former US Vice President Joseph R. Biden Jr. participate of the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019. SAUL LOEB/AFP/Getty Images

Democratic presidential candidates Sen. Kristen Gillibrand, D-N.Y., left, Sen. Michael Bennet, D-Colo., and Rep. Eric Swalwell, D-Calif., stand on stage before a Democratic primary debate hosted by NBC News at the Adrienne Arsht Center for the Performing Arts, Thursday, June 27, 2019, in Miami.

Former tech executive Andrew Yang reacts during the second night of the first Democratic presidential debate on June 27, 2019 in Miami, Florida. A field of 20 Democratic presidential candidates was split into two groups of 10 for the first debate of the 2020 election, taking place over two nights at Knight Concert Hall of the Adrienne Arsht Center for the Performing Arts of Miami-Dade County, hosted by NBC News, MSNBC, and Telemundo.

Democratic presidential hopeful former Governor of Colorado John Hickenlooper speaks during the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019. SAUL LOEB/AFP/Getty Images

Democratic presidential candidate Sen. Kamala Harris (D-CA) speaks during the second night of the first Democratic presidential debate on June 27 in Miami.

Democratic presidential hopefuls Former US Vice President Joseph R. Biden (R) and Mayor of South Bend, Indiana Pete Buttigieg (L) speak on stage for the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019. SAUL LOEB/AFP/Getty Images

Democratic presidential hopefuls (L-R) US author and writer Marianne Williamson, Former Governor of Colorado John Hickenlooper and US entrepreneur Andrew Yang speak in the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019. SAUL LOEB/AFP/Getty Images

Democratic presidential candidate entrepreneur Andrew Yang, right, speaks during the Democratic primary debate hosted by NBC News at the Adrienne Arsht Center for the Performing Arts, Thursday, June 27, 2019, in Miami, as former Colorado Gov. John Hickenlooper listens.

Democratic presidential hopefuls (L-R) former Vice President Joseph R. Biden Jr., senator for Vermont Bernie Sanders and senator for California Kamala Harris arrive on stage for the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019.

Democratic presidential candidate and former Colorado Gov. John Hickenlooper, right, speaks during the Democratic primary debate hosted by NBC News at the Adrienne Arsht Center for the Performing Arts, Thursday, June 27, 2019, in Miami, as author Marianne Williamson watches.

Democratic presidential hopefuls (from L) US author and writer Marianne Williamson, former Governor of Colorado John Hickenlooper, US attorney and entrepreneur Andrew Yang, Mayor of South Bend, Indiana Pete Buttigieg, former US Vice President Joseph R. Biden, US Senator for Vermont Bernie Sanders, US Senator for California Kamala Harris, US Senator for New York Kirsten Gillibrand, US Senator for Colorado Michael Bennet, US Representative for California's 15th congressional district Eric Swalwell, participate in the second Democratic primary debate of the 2020 presidential campaign season hosted by NBC News at the Adrienne Arsht Center for the Performing Arts in Miami, Florida, June 27, 2019.

Democratic presidential candidates (L-R) Marianne Williamson, former Colorado governor John Hickenlooper, former tech executive Andrew Yang, South Bend, Indiana Mayor Pete Buttigieg, former Vice President Joe Biden, Sen. Bernie Sanders (I-VT), Sen. Kamala Harris (D-CA), Sen. Kirsten Gillibrand (D-NY), Sen. Michael Bennet (D-CO), and Rep. Eric Swalwell (D-CA) take the stage during the second night of the first Democratic presidential debate on June 27, 2019 in Miami, Florida. A field of 20 Democratic presidential candidates was split into two groups of 10 for the first debate of the 2020 election, taking place over two nights at Knight Concert Hall of the Adrienne Arsht Center for the Performing Arts of Miami-Dade County, hosted by NBC News, MSNBC, and Telemundo.

former Vice President Joe Biden and Sen. Bernie Sanders (I-VT) take the stage for the second night of the first Democratic presidential debate on June 27, 2019 in Miami, Florida. A field of 20 Democratic presidential candidates was split into two groups of 10 for the first debate of the 2020 election, taking place over two nights at Knight Concert Hall of the Adrienne Arsht Center for the Performing Arts of Miami-Dade County, hosted by NBC News, MSNBC, and Telemundo.

Democratic presidential candidates (L-R) Marianne Williamson, former Colorado governor John Hickenlooper, former tech executive Andrew Yang, South Bend, Indiana Mayor Pete Buttigieg, former Vice President Joe Biden, Sen. Bernie Sanders (I-VT), Sen. Kamala Harris (D-CA), Sen. Kirsten Gillibrand (D-NY), Sen. Michael Bennet (D-CO), and Rep. Eric Swalwell (D-CA) take the stage during the second night of the first Democratic presidential debate on June 27, 2019 in Miami, Florida. A field of 20 Democratic presidential candidates was split into two groups of 10 for the first debate of the 2020 election, taking place over two nights at Knight Concert Hall of the Adrienne Arsht Center for the Performing Arts of Miami-Dade County, hosted by NBC News, MSNBC, and Telemundo.