Heitkamp, Manchin, McCaskill, Jones, and one other I can't remember.
Also, Lindsay Graham was opposed as well. Graham and Flake were promised a DACA vote during the tax talks, Paul thinks the amount of money for the Wall is crazy. McCain is obviously out.
From everything I can gather, the issue is actually Stephen Miller and John Kelly. Trump has tried to make a couple deals, but then they talk him out of it by sending in the Freedom Caucus from the House. Lindsay Graham has been especially critical of Kelly and Miller the last few days.