Rick Santorum has come to the aide of Chick-Fil-A, defending the chicken restaurant from criticism expressed by Mayors Thomas Menino of Boston and Rahm Emanuel of Chicago.

After Chick-Fil-A President Dan Cathy conceded that his company is opposed to gay marriage and supports groups opposed to the institution (donating $5 million between 2003 and 2010), Menino wrote a scathing letter to Cathy in which he said that his fast-food chain was not welcome in Boston.

“I was angry to learn on the heels of your prejudiced statements about your search for a site to locate in Boston. There is no place for discrimination on Boston's Freedom Trail and no place for your company alongside it. When Massachusetts became the first state in the country to recognize equal marriage rights, I personally stood on City Hall Plaza to greet same sex couples coming here to be married. It would be an insult to them and to our city's long history of expanding freedom to have a Chick-fil-A across the street from that spot,” Menino wrote.

Emanuel piled on, saying: “Chick-Fil-A's values are not Chicago values. They're not respectful of our residents, our neighbors and our family members. And if you're gonna be part of the Chicago community, you should reflect Chicago values.”

Menino and Emanuel are co-chairs of the group Mayors for the Freedom to Marry.

Appearing on CNBC's Kudlow Report, Santorum criticized the mayors, calling their comments “hateful.”

"You just keep seeing this more and more, which is the absolute intolerance of the left in America. There can be no dissent from what their position is. If you dissent, if you disagree, you are to be punished. You are to be castigated. You are to be barred from doing business.”

"This is why the Huguenots came to America, this is why the Dutch reform, the Catholics – so many came to this country because they wanted religious freedom. They didn't want the government telling them what to believe in. That they couldn't say things in public. That they had to keep it to themselves. And if they didn't do that that they would lose privileges, that they would lose the opportunity to make a living.”

"This is not America, and this is why I think you're seeing such a backlash to these hateful comments by the part of these city leaders."

(Related: Rick Santorum supports Mike Huckabee's “Chick-Fil-A Appreciation Day.”)