1. George W. Bush AND Bush Sr.
Both former Bush presidents, George H.W Bush and son George W. Bush, don’t support the billionaire businessman, despite endorsing previous GOP’s general election candidates.
Spokesmen for both former commanders-in-chief said the two Bush statesmen would make no comment about Trump's campaign, nor would they participate in support of it. Both previously endorsed Mitt Romney in the 2012 race and John McCain back in 2008.
…but we're just getting started. Next up on our list is a certain Senator who won't back Trump: