Fresh off back-to-back victories in the Republican presidential race, Donald Trump is moving to expand his tight-knit campaign by building a political kitchen cabinet that includes former New York mayor Rudolph W. Giuliani. Giuliani, who has not made an endorsement in the 2016 contest, said in an interview Sunday that he has conferred at length with Trump at least three times in the past month, both in person and by phone, and has counseled the real estate mogul "as a close personal friend" about campaign issues. "We've been talking. Donald and me, Donald and a few other friends who know...