Senate Majority Leader Harry Reid (D-Nev.) postponed a crucial vote on the financial regulatory overhaul measure Wednesday afternoon, so he could shore up votes among his own party for bringing debate to a close.

Several Senate Democrats were withholding their support for a filibuster-breaking vote that was to take place at 2 p.m. Wednesday because they could not secure agreements to vote on their amendments.

Reid scheduled a Senate Democratic caucus meeting for 2:15 p.m. instead. It was unclear when the vote to invoke cloture — which requires 60 votes to approve — would actually take place.

Sen. Carl Levin (D-Mich.) blocked Banking Chairman Chris Dodd (D-Conn.) from entering into an agreement that would have allowed votes on two Democratic amendments and one GOP-sponsored proposal.

It was unclear why Levin took such a tack, since he and Sen. Jeff Merkley (D-Ore.) decided earlier in the day to try to force a vote on their bank proprietary trading ban by offering the language as a second-degree amendment to a Sen. Sam Brownback (R-Kan.) proposal. That strategy is likely to secure the duo’s ability to hold a vote on the amendment before final passage of the bill, sources said.

Levin’s objection blocked Sen. Sheldon Whitehouse from getting a vote on his amendment to allow states to regulate credit card rates marketed within their borders. The Rhode Island Democrat has been on the floor for most of the day Wednesday trying to ensure his proposal gets a vote.