Caesars Entertainment Corp. is the closest it's been to ending two years of rancorous court battles with bondholders over who should pay to fix the casino giant's insolvent operating unit, which can't afford to pay almost $20 billion in debt.

The company is giving creditors until midnight in New York to accept a sweetened offer of more than $5 billion in cash, new debt and stock in a reorganized company. A group of bondholders that have been the biggest obstacle to the company's plan has agreed on the framework of a deal, people familiar with the talks said Thursday.

Now the question will be whether the company's more senior lenders — who were on board with previous iterations of the plan — will be willing to give up some of the gains they won at the negotiating table in order to get the plan approved. Those creditors, who hold Caesars' bank loans and first-lien bonds, would need to give up "hundreds of millions of dollars" in recoveries, according to the offer Caesars disclosed Wednesday. At least some senior lenders were hesitating on Thursday, said the people, who asked not to be identified because the discussions are private.