Democratic congressman Phil Hare of Illinois has become the first member of Congress to call for Burris to step down.
"I am deeply disappointed that Senator Burris hid the fact that he attempted to raise money for former Governor Blagojevich at the same time he was lobbying for an appointment to the U.S. Senate," the representative said in a statement.
"I believe it is in the best interest of all Illinoisans that Senator Burris resigns," he added, bemoaning that "a cloud of corruption has hung over our state and its leaders for too long."
Earlier in the day, while traveling in Athens, Greece, Burris' Senate colleague Senator Dick Durbin (D-IL) said, "the public statements made by Mr. Burris to this point have raised questions which need to be looked at very carefully," according to the Associated Press.
"His sworn testimony in Springfield did not satisfy our requirement in that it was not complete and we need to have the complete story before the final conclusion that we reach," Durbin added. He stopped short of calling for Illinois' junior senator to resign.
Burris now faces a perjury investigation. An affidavit from the senator prior to his confirmation said that Burris had told Governor Rod Blagojevich's brother that he could not raise money for the governor because, "it could be viewed as an attempt to curry favor with him regarding his decision to appoint a successor to President Obama."
Monday night, however, the senator told reporters that he "talked to some people about trying to see if we could put a fundraiser on." The question now is whether intent to fundraise for the governor is punishable.
In a Chicago press conference this afternoon, Burris said he would fully cooperate with the investigation and would "welcome" the opportunity to answer renewed questions from authorities and elected officials, the AP reports. He added, however, that he would no longer speak to the press.
In an editorial this morning, Burris' hometown newspaper, the Chicago Tribune, called for the embattled senator to resign.
"The benefit of the doubt had already been stretched thin and taut by the time Roland Burris offered his third version of the events leading to his appointment to the U.S. Senate. It finally snapped like a rubber band, popping him on that long Pinocchio nose of his, when he came out with version four. ... The story gets worse with every telling. Enough. Roland Burris must resign," the editorial said.