JOHANNESBURG (Reuters) - A top shareholder in Darty Plc (>> Darty PLC) will back Steinhoff's (>> Steinhoff International Holdings NV) $975 million takeover bid for the French electronic goods retailer, the South African furniture group said Monday.

Steinhoff said its offer had the support of Schroder Investment Management, a British hedge fund firm. Schroder owns about 14 percent of Europe's third-largest electronics retailer, making it the biggest shareholder.

Investors have until May 2 to accept the offer, which trumped a competing bid from French retailer Fnac (>> GROUPE FNAC) last month and has the backing of Darty's board.

The transaction would bulk up Steinhoff's presence in Europe, where it already makes more than two-thirds of its 9.8 billion euros ($11.18 billion) of annual sales.

Darty earns 70 percent of its revenue in France but has 400 stores across Europe and competes with Media-Saturn, owned by Germany's Metro (>> METRO AG), and with Britain's Dixons . Steinhoff's Conforama, like Darty and Fnac, has a strong presence in French high streets and retail parks.

(This version of the story removes the incorrect reference in the second paragraph saying Steinhoff is the biggest retailer by market capitalisation.)

(Reporting by Tiisetso Motsoeneng; editing by Susan Thomas)