NEW YORK, APRIL 16 - Bill Weld, the former governor of Massachusetts, is the first Republican candidate to take the field for the 2020 elections and challenge Donald Trump. Trump critic, Weld announces his candidacy with a video: "It's time to go back to the principles of Lincoln, equality, dignity and opportunities for all. There is no better cause in the world than preserving what makes America really great "I am ready to lead this battle."