Senate Majority Leader Harry M. Reid's decision to bring to the chamber's floor a healthcare bill containing a government insurance plan was met with skepticism by moderate Democrats, who said they still do not know whether they could support a public option on a final vote. Democrats expect Reid to attempt to secure commitments from all 60 members of his caucus to allow the Senate to begin debate on the legislation, aimed at lowering healthcare costs, reforming insurance practices, and expanding coverage to about 30 million uninsured Americans.