(CNN) President Donald Trump is expected to finalize his choice for the Supreme Court by Thursday or Friday, two people familiar with the search say, allowing aides in a newly minted White House war room to spend the weekend preparing for a summer confirmation fight.

In this leak-prone White House, the President's choice will be guarded as closely as a wartime command. His decision will be included on a larger list of finalists, with at least two -- possibly three -- names shared with members of the administration's Supreme Court confirmation team.

This also allows the President to change his mind before he introduces his next Supreme Court nominee from the White House on Monday evening, aides say.

An eleventh-hour lobbying campaign is furiously underway, with the President and his team fielding calls from senators, conservative activists, donors and friends who are trying to argue the case for or against one of the leading contenders.

Even though the federal government is closed for Independence Day, aides said, the President is expected to take calls and speak with people about the search throughout the day and even into evening at his July 4th party at the White House. Officials have made it clear that time is running out for senators to convey their thoughts to the President before he makes his pick.

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