By Jesse Byrnes
Sen. John McCainJohn McCainWhich GOP pols will actually attend the convention? Trump bucks military on waterboarding Overnight Defense: Pentagon lifts transgender ban | Navy says Iran broke law by detaining sailors MORE (R-Ariz.) offered his colleague Sen. Ted CruzTed CruzThe Hill's 12:30 Report Trump hires Florida chief strategist, new pollster Lynch pressured to recuse herself after Clinton tarmac meeting MORE a non-endorsement on the eve of the Texas Republican's expected presidential launch.
And if Cruz ultimately wins the nomination, he could beat Hillary Clinton and go all the way in 2016, McCain suggested.
But McCain pointed out his deepest support remains with his friend and potential 2016 Republican presidential contender, Sen. Lindsey Graham (R-S.C.).
"Lindsey Graham is the one I think knows best about national security," McCain said.
Cruz is expected to announce his White House bid Monday during a speech at the evangelical Liberty University.