In this Oct. 17, 2019, photo, President Donald Trump speaks during a campaign rally at the American Airlines Center in Dallas. (AP Photo/Jeffrey McWhorter)

Turkish soldiers stand in attention during a ceremony for soldier Sefa Findik, killed in action with Kurdish fighters in Syria earlier Sunday, during a ceremony at the airport in Sanliurfa southeastern Turkey, Sunday, Oct. 20, 2019.It brings Turkey's military death toll up to seven soldiers in its wide-ranging offensive against Syrian Kurdish forces. (AP Photo/Lefteris Pitarakis)

Democratic presidential candidate Sen. Bernie Sanders, I-Vt., left, former Vice President Joe Biden, center, and Sen. Elizabeth Warren, D-Mass., raise their hands to speak during a Democratic presidential primary debate hosted by CNN/New York Times at Otterbein University, Tuesday, Oct. 15, 2019, in Westerville, Ohio. (AP Photo/John Minchillo)

Democratic presidential candidate Sen. Amy Klobuchar, D-Minn., responds to questions following a Democratic presidential primary debate hosted by CNN/New York Times at Otterbein University, Tuesday, Oct. 15, 2019, in Westerville, Ohio. (AP Photo/Tony Dejak)

Democratic presidential candidate former Housing Secretary Julian Castro walks to be interviewed following a Democratic presidential primary debate hosted by CNN/New York Times at Otterbein University, Tuesday, Oct. 15, 2019, in Westerville, Ohio. (AP Photo/Tony Dejak)

Democratic presidential candidate Sen. Bernie Sanders, I-Vt., left, former Vice President Joe Biden and Sen. Elizabeth Warren, D-Mass., right, participate in a Democratic presidential primary debate hosted by CNN/New York Times at Otterbein University, Tuesday, Oct. 15, 2019, in Westerville, Ohio. (AP Photo/John Minchillo)