SAN FRANCISCO – The battle for Dell Inc. moved into a new, crucial phase Thursday as Michael Dell's camp was given another week to round up votes for his proposed $24.4 billion takeover even as he was said to remain adamant about not sweetening his $13.65-a-share offer.

Facing almost certain defeat of the leveraged buyout, the Dell board postponed a shareholder meeting Thursday morning until July 24, a move that would allow Dell more time to persuade investors to change their minds or corral the 23 percent of eligible voters said to have abstained from casting ballots.

Chief Executive Dell and Silver Lake Management need a majority of holders to vote in favor of their transaction, excluding the CEO's 16 percent stake. As of Thursday morning, Dell hadn't lined up all of the 42 percent, or about 740 million shares, needed to prevail.

"There is going to be a lot of arm-twisting," Jason Subotky, senior vice president at Yacktman Asset Management Co., said in an interview on Bloomberg Television. He said the founder's offer is too low. "They are going to be pounding the shareholders to change votes and get people to vote."

While opponents including Carl Icahn and Yacktman are pressing for a higher price, Michael Dell isn't seeking more financing from Microsoft Corp. or the banks that secured debt for the deal, according to people familiar with the situation.

The current bid calls for Michael Dell to roll over about $3.6 billion of Dell stock and to contribute as much as another $750 million in fresh cash.

"The challenge this week for Dell and Silver Lake is to get out and contact shareholders, especially those who abstained today," said Jeff Fidacaro, an analyst at Monness Crespi Hardt & Co. "It's going to get down to the wire."

The proposal Dell and Silver Lake put to a shareholder vote represents a premium of 25 percent over the computer maker's closing share price of $10.88 on Jan. 11, the last trading day before news of the deal.

Leading the charge against the deal is Icahn, who has made a series of offers aimed at blocking the buyout.