Erin Burnett Outfront

Whistleblower memo: White House official who listened to Ukraine call was "shaken" by it, described it as "crazy" and "frightening"; White House tells Pelosi Trump won't cooperate with "illegitimate" impeachment process; White House letter: Trump won't participate in impeachment inquiry; Schiff on White House calling impeachment inquiry "illegitimate": White House is trying to argue "The President is above the law"; White House letter calls impeachment inquiry "baseless" and "unconstitutional"; says it violates Trump's due process; Democrats subpoena Sondland after White House orders him to testify; Trump confidant: impeachment a "mortal threat" to his presidency; Bernie Sanders scaling back campaign schedule after heart attack; Sanders says he is "changing the nature" of his campaign after suffering a heart attack; Kamala Harris betting big on Iowa; aiming to finish in top three; Kamala Harris r