There is no deal that would get his support.
It should come as no surprise that Republicans are "against" the Iran deal. They were against having the negotiations in the first place. They are against anything the not-Republican administration does, and it does not make a damn bit of difference what, and they do not need to know what the deal might be in order to know that they are against it, period, full stop, because they can only presume that because it was done by the not-Republican administration it's a very terrible thing that only a madman would support.
And so the Senate hearings on "the deal" of course started out ridiculous and just kept going.
“We’ve been through an incredible journey that began 20 months ago” when Iran “was a rogue nation that had a boot on its neck,” Senate Foreign Relations Committee Chairman Bob Corker (R-Tenn.) said. “Our goal was to dismantle their [nuclear] program.”
Instead, he said, “the deal on the table basically codifies the industrialization of their nuclear program. An amazing transition has occurred.” [...]
Earlier in the day, House Speaker John A. Boehner (R-Ohio) said the questions would be tough, but he appeared to have already made up his mind, saying that “a bad deal threatens the security of the American people, and we’re going to do everything possible to stop it.”
Good on Boehner for not even bothering with hearings before deciding that the administration was "threatening the security" of the nation. House Republicans are nothing if not efficient.
All of this could be justifiable, in some fashion, if Republicans could elucidate what their imaginary better deal would look like and, conspicuously, how they would coax the foreign nation of Iran, a nation keenly aware of its position in the crosshairs of American hawks not fully sated by the two wars let loose just over Iranian borders, to give those things up. But there is no "better deal." The position is that there should be no deal at all, because anything that does not result in the United States bombing Iran until Iran surrenders to U.S. demands is "weak."
[The Republican position] assumes that when dealing with adversaries like Iran, negotiation is weak, again by definition. Negotiation means talking to those we hate, and even offering them concessions. Successful negotiation ends with an outcome that our adversaries actually praise, when what we really want is for them to fall to their knees and surrender to our might. This is what elected Republicans believe, and more importantly, it’s what they’ve been telling their constituents for years, so it’s what those constituents demand.
The Republican position should be, if any of us truly believe it to be sincere, frightening. On the heels of declaring the international righteousness of
preventative war, then mounting that war, the movement has set sights on the principle that the nation of Iran, too, poses a potential future threat that can only be relieved when that irritatingly too-sovereign nation surrenders unconditionally to whatever demands the Republican Party imagines themselves to have for it. Not the international community; not the United Nations; not the sitting American administration itself. They will suffer no negotiations by any world force other than whichever Republican president they imagine will next hold the office—and each of the current candidates is quite sure that they will either
make Iran surrender without condition, or American soldiers that they have never met will die trying.