New York City ? Wall Street became increasingly skittish about Rupert Murdoch’s prospects for clinching a deal to buy Dow Jones & Co., sending the stock of The Wall Street Journal publisher down more than 5 percent Monday as a deadline arrived for the Journal’s controlling shareholders to make a decision.

Members of the Bancroft family, which has controlled Dow Jones for a century, had a 5 p.m. deadline Monday to tell the family’s lead trustee how they would vote on Murdoch’s $5 billion offer to buy the company.

On Monday a News Corp. spokesman said the company was “highly unlikely” to go ahead with the deal if the level of support among the Bancrofts remained at just 28 percent of the shareholder vote, which The Wall Street Journal reported was the level of commitment as of Sunday.