The Senate on Thursday took up and then abruptly dropped a test of President Barack Obama’s bid to take the sting out of the debt limit, providing a brief public showdown over an issue linked to fiscal cliff negotiations.

The matter fell apart when Republicans objected to a straight majority vote on a debt ceiling plan that Senate Minority Leader Mitch McConnell, R-Ky., had brought to the floor.

McConnell had sought the vote on a White House proposal to give the president what would amount to unlimited authority to raise the statutory limits on federal borrowing.

But McConnell, who was seemingly reviving a legislative tactic of pushing Democrats into politically tough votes, later effectively rejected an offer by Senate Majority Leader Harry Reid, D-Nev., to hold the vote Thursday afternoon. McConnell insisted on a 60 vote-threshold for passage, something Reid refused, ending the matter for the moment while leaving many senators looking confused about the rapid maneuvering on the floor.

The actions suggested that Democrats have a solid bloc of votes on at least one fiscal cliff issue that may have divided liberals from more conservative members.

A Senate Democratic aide said Thursday he was “very confident” that Democrats would have had the 51 votes needed on a simple-majority vote. Before the vote was called off, conservative Democrat Ben Nelson of Nebraska said he would back the proposal to take the threat of a government default off the table in fiscal negotiations.

Under the administration’s plan, once the president requests an increase in the debt ceiling, Congress would have 15 days to enact a joint resolution of disapproval. If both chambers passed the resolution, it would be sent to the president, who could sign or veto it. If the president vetoed the resolution, the government’s borrowing capacity would increase absent a vote to override the veto, requiring two-thirds support in each chamber.

Administration officials call it the “McConnell provision” because McConnell had proposed it as part of the 2011 law (PL 112-25) that raised the debt ceiling.

McConnell initially may have believed that he had put Democrats in a tough position by calling for a vote.

“I would hope that we can work together here and get a vote on it and give his members a chance to express themselves as to whether or not they think that’s a good way forward for our country, to give this president or any other president unlimited authority to borrow as much as he wants at any time he wants from the Chinese or anybody else,” McConnell said Thursday morning.

Afterwards, Democrats chided McConnell for the reversal.

“This may be a moment in Senate history, when a senator made a proposal and when given an opportunity for a vote on that proposal filibustered his own proposal,” said Senate Majority Whip Richard J. Durbin, D-Ill.

White House Press Secretary Jay Carney, meanwhile, shot down the idea that Obama would simply ignore the debt ceiling on his own through the 14th Amendment, which says that the debt of the United States shall not be questioned.

“This administration does not believe that the 14th Amendment gives the president the power to ignore the debt ceiling. Period.”

Carney called on Congress to “do its job” and make sure that the nation’s bills are paid, noting that the debt limit does not authorize new spending but simply allows for spending that Congress has already passed into law.

Steven T. Dennis and Meredith Shiner contributed to this report.