Financial notices posted last night said the Greenock businessman, who runs bus firm McGills with brother James, has secured proxy votes totalling almost 24% in the Ibrox club.
Mr Easdale previously increased his own stake to 4.4%, and is now in charge of a block of shares belonging to institutional investors.
A stock exchange statement said that Mr Easdale had been granted the voting rights of Blue Pitch Holdings and Margarita Funds Holding Trust.
It said: "As a result, including the Ordinary Shares held directly by Mr Easdale, being 2,842,957 Ordinary Shares representing 4.37% of the issued share capital of the Company, Mr Easdale has voting rights over, in aggregate, 15,484,295 Ordinary Shares representing 23.79% of the issued share capital of the Company."
The announcement, which confirmed reports from earlier in the week, marks another twist in the power struggle at Ibrox Stadium.
A group of disgruntled Rangers shareholders who had demanded an extraordinary meeting and the removal of chief executive Craig Mather withdrew their request last week.
The group, which included businessman Jim McColl, also wanted directors Brian Stockbridge and Bryan Smart to stand down from the board of Rangers International Football Club PLC, which is the parent company of The Rangers Football Club Ltd.