Shares of insurance companies like Aetna (AET) , UnitedHealth (UNH - Get Report) , Cigna (CIG - Get Report) and Humana (HUM - Get Report) rose slightly following the Senate's unveiling of health care reform.

Joel White, president of the Council for Affordable Health Care, said it's too early to tell if the bill will pass, but that the bill can lose two Republican Senators and still pass, assuming no Democrats support the bill. 

"We don't have an official score on the bill yet," White said, referring to the Congressional Budget Office rating, which estimated that 23 million people would lose coverage under the House version of health care reform, passed in May.