Two Democrats added Jeff Flake to the not-so-exclusive club after he criticized Donald Trump.
The chorus of GOP Senators speaking out against Trump exposes deep divides ahead of the 2018 midterms.
Senator Corker called President Trump harmful and said he is "absolutely not" a role model for the country.
One of the top Republicans is becoming even more outspoken against Trump after announcing his retirement.
Tillerson also wants to remove an envoy for the closure of Guantánamo Bay.
John McCain and Bob Corker both criticized Obama Wednesday after news broke that Russia has bombed non-ISIL targets inside Syria.