Arizona Sen. John McCain took to the Senate floor on Wednesday to call out a fellow Republican lawmaker for "specious and degrading attacks" which allege that Secretary of State Hillary Clinton's deputy chief of staff had infiltrated the U.S. government on behalf of radical Islamists in the Muslim Brotherhood.

Last week, the St. Cloud Times reported the Minnesota Rep. Michele Bachmann and four other Republicans had called on inspectors general in the State, Homeland Security, Defense and Justice departments to investigate "potential Muslim Brotherhood infiltration" of the Obama administration by Huma Abedin, an aide to Secretary Clinton and wife of former Rep. Anthony Weiner (D-NY).

"It has been alleged that Huma Abedin, a Muslim American, is part of a nefarious conspiracy to harm the United States," McCain explained on Wednesday, noting that the accusations were based on an "unsubstantiated" report by Frank Gaffney's neoconservative Center for Security Policy.

"The allegations about Huma Abedin and the report from which they are drawn are nothing less than an unwarranted and unfounded attack on an honorable citizen, a dedicated American and a loyal public servant," the Arizona senator continued. "These attacks have no logic, no basis and no merit. And they need to stop. They need to stop now."

"When anyone -- not least, a member of Congress -- launches specious and degrading attacks against fellow Americans on the basis of nothing more than fear of who they are and ignorance of what they stand for, it defames the spirit of our nation and we all grow poorer because of it," he added.

Rep. Keith Ellison (D-MN) on Tuesday described Bachmann’s attack on Abedin as the “worst” type of “guilt by association” and a “stark affront to American values.”

Watch this video from the C-SPAN, broadcast July 18, 2012.