(CNN) - As votes were tallied Wednesday in a dramatic Senate vote to move ahead with the debt ceiling bill, some senators' votes were not read aloud by the clerks, breaking from the usual protocol of disclosing each senator's vote in real time.
A spokesman for Senate Majority Leader Harry Reid said Senate clerks were asked not to read the names, so Republicans could feel more free to vote or change their votes as some GOP leaders sought to bring enough senators on board to end Sen. Ted Cruz’s filibuster that threatened to lead to a politically damaging fight over raising the debt limit.
"After the vote began, it was quickly clear that Republican leaders were struggling to deliver enough votes to clear the 60-vote hurdle upon which they had insisted instead of a simple majority, and a potentially catastrophic default suddenly seemed possible," Reid spokesman Adam Jentleson said in a statement.
"At Senate Republicans' request, the clerk did not call the names during the vote to make it easier for Republican leaders to convince their members to switch their votes."
CNN was not able to get a response from Senate Republicans to confirm they had requested the names not be read out loud.
Many of those same Republicans ended up voting against the bill in the end, but this time their names were read aloud so they could be on the record voting against raising the debt ceiling.
The previous vote was simply a vote to move ahead to the final vote. It could easily be used by political opponents in ads to say the Republican senator voted "aye" on a bill to raise the debt ceiling.
In fact, a primary challenger running against Senate Minority Leader Mitch McConnell, who's up for re-election this year, immediately released a statement criticizing McConnell for voting in favor of moving ahead with the bill–even though McConnell voted against raising the debt ceiling in the end.
Reporters filed transparency complaints with Reid's office, but his spokesman said "such a request is consistent with Senate rules."
CNN's Ted Barrett and Ashley Killough contributed to this report.