Originally Posted by
cobra_king
Aside from the fact that the runner on 1st should never allow this to happen, the answer to your question would be that the 2nd runner who left from first base would be considered safe as long as he never passed the runner in front of him. The ball would be considered live and in play as long as the umpire did not call time, and having a collision at home plate with a runner immediately behind him would not be a reason for time to be called. The final result would be the run scoring and the home team winning.