From NBC's Kelly O'Donnell
Democratic sources say the president's letter to leaders on Capitol Hill will be sent shortly.
President Obama will ask them to consider four areas that Republicans suggested:
-- Medicare Fraud (Coburn)
-- Medical Malpractice
-- Health Savings Accounts
-- Upping reimbursement to doctors who see Medicaid patients (Grassley)
The president is expected to tell Congress he supports a comprehensive approach and that he does not believe "piece meal" will work.
He will say good things about the Blair House Summit and everyone's participation.