"I think it was outside the realm of Senate behavior," said Sen. John McCain, R-Arizona, who has clashed with Cruz in the past. "I would never contemplate going to the floor of the Senate and impugning the integrity of another senator. Just not something we do here. I really think it was a very wrong thing to do."
"Squabbling and sanctimony may be tolerated in other venues -- or perhaps on the campaign trail -- but they have no place among colleagues in the United States Senate," warned Sen. Orrin Hatch of Utah in a lengthy floor speech reprimanding Cruz.
As President Pro Tempore of the Senate, Hatch was tasked by GOP leaders with formally responding to the caustic nature of Cruz's speech on Friday, which many believe violated a Senate rule against impugning the integrity of a fellow senator.
During the rare Sunday session, which was called for votes on a highway funding bill, McConnell responded publicly for the first time and denied he misled anyone.
"I've said repeatedly and publicly for months that the Ex-Im supporters from both parties should be allowed a vote. I also said publicly that the highway bill would be an obvious place to have that vote," McConnell said. "When there is overwhelming bipartisan support for an idea, even if I oppose it, it doesn't require some 'special deal' to see a vote occur on the measure. This is the United States Senate, after all, where we debate and vote on all kinds of different issues."
In other setbacks for Cruz, a GOP presidential candidate who polls in the low single digits, the Senate then voted overwhelmingly in favor of the Export-Import Bank, an institution Cruz complains is an example of Washington corporate welfare. Senators then refused to grant Cruz a roll call vote on a Senate rules change he was proposing that could have allowed him to offer an amendment related to the Iran nuclear deal.
Despite the heavy criticism, Cruz didn't back down.
"I do not believe speaking the truth is anything other than in the very best tradition of the United States Senate," Cruz told reporters after the vote when he was asked if he regretted going too far in calling McConnell a liar.
On Friday, Cruz gave a long floor speech in which he laid out his contention that McConnell promised Republican senators, in a closed meeting, that there was not a deal to give supporters of the Export-Import Bank a vote to restart it in return for their votes on the a recent trade bill. He reiterated Sunday that McConnell went back on his word and used his authority as majority leader to set up a vote on the highway funding bill that the Senate is currently debating.
"Those were extraordinary steps designed to force a vote to reauthorize the Export-Import Bank and they were directly contrary to the promises the Majority Leader made to 53 Republicans and to the press," Cruz said Sunday. "My saying so is uncomfortable but it is a simple fact entirely consistent with decorum and no member of this body has disputed that promise was made and that promise was broken."
However, other GOP senators do dispute Cruz's recollection of events.
"I would have to say he's mistaken," said Sen. John Cornyn, the number two GOP senator and the senior senator from Texas. "If, in fact, the Majority Leader had somehow misrepresented to 54 senators what the facts were with the ex-im bank, I suspect that you would find out her voices joining that of the junior senator but I hear no one else making such a similar accusation."
Senators of both parties, who resented getting dragged into work on a Sunday, said the smell of presidential politics was in the air.
Senate Democratic Leader Harry Reid said Cruz and others were trying to "garner the affection of the Koch brothers," the billionaire Republican donors.
"After all, opposition the Export-Import Bank is a prerequisite for any Republican running for president," Reid said.