Below, is a list of 16 States won by Tump, that can not force an Electoral College Elector to vote for Trump. In most states, the Electoral College Electors vote anonymously. During the Republican Primary many of the Electors supported candidates other than Trump. Currently, Trump has a projected 279 Electoral College Votes. It is reasonable to believe that by December 19th, there can be at least a total of 10 Electors, from among these 15 states, willing to cast their Electoral College Vote for a Republican other than Trump. That would keep Trump under the 270 required to win the Presidency.
*New Hampshire is too close to call, and has not yet been officially declared for either candidate.