Caesars Entertainment Corp. won more support for a plan to put its biggest unit into bankruptcy as soon as next week after a bondholder group that’s already on board with the restructuring bought $500 million of debt from BlackRock Inc., Bloomberg News reported today. Caesars, owned by Apollo Global Management LLC and TPG Capital, has been negotiating with creditors for four months on a plan to reorganize Caesars Entertainment Operating Co., the subsidiary that owns most of its casinos. Its proposal would restructure $18.4 billion of debt by putting the unit into bankruptcy as soon as Jan. 15 and turning it into a real estate investment trust.