At a luncheon in February 2016 attended by Republican governors and donors, Karl Rove discussed the danger of Trump securing the Republican nomination in July, and that it may be possible to stop him, but that there was not much time left [REF].
Early in March 2016, Mitt Romney, the 2012 Republican presidential nominee, directed some of his advisors to look at ways to stop Trump from obtaining the nomination at the Republican National Convention (RNC).