question for the history buffs....has any sitting supreme court justice ever resigned to run for president (or any other political office).
Charles Hughes (GOP candidate from 1912) was a Supreme Court Justice at one time.
1916 Phil. 
Hughes was a terrible canddiate. He didn't know how to act. He did not meet with Governor Johnson (which would have assured California, and thus the race). He nearly tied himself to the pro-War Teddy Roosevelt, and he ran as the "I'm not Woodrow Wilson" Candidate.
How could I make that mistake? Seriously. That's an embarrassment. I know the elections and the candidates like the back of my hand! I remember once when a friend was quizzing me on who ran in certain elections. He asked me about 1948 and I said "There was no election in '48. It was in '46." Embarrassing.
Anyway, I don't know how strong Hughes was but he couldn't have been that bad. He made that one close election.
The factor that hurt Hughes the most was World War One. The United States had not yet entered the war, and Wilson ran on the famous "he kept us out of the war" slogan. Democrats took out full page ads in major newspapers around the country (there was not yet any radio) declaring "If you want war, vote for Hughes. If you want peace, vote for Wilson." Wilson barely won and the US entered the war a few months after Wilson's second inauguration.
