Exxon Mobil CEO Rex Tillerson has emerged as the frontrunner to be Donald Trump’s choice for Secretary of State. However, unlike many other choices Trump chose for cabinet posts, Tillerson is not getting a collective thumbs up from others in the GOP. The hit on Tillerson is that he’s too chummy with Russian President Vladimir Putin (Putin once awarded Tillerson an ‘Order of Friendship’ medal in 2013). Senators John McCain, Rand Paul, Bob Corker and Lindsey Graham have all expressed concerns over Tillerson.

Now Marco Rubio has stepped forward to say something. He has done it via Twitter:

Being a "friend of Vladimir" is not an attribute I am hoping for from a #SecretaryOfState – MR

— Marco Rubio (@marcorubio) December 11, 2016

Trump will likely have a Twitter tantrum at first, but he won’t want to be embarrassed to see his nominee voted down on the Senate floor and Tillerson won’t want that either.

How this plays out, will certainly be interesting.

UPDATE: An earlier version of this article identified Maine Senator Susan Collins as one of the Senators who has expressed concern over Tillerson’s possible nomination. That was incorrect. – JC