WASHINGTON, Jan. 16 — President Bush is expected to propose a health care initiative in his State of the Union address to help the uninsured and the underinsured, White House advisers said on Friday. It was unclear how much the initiative, to be announced in the address on Tuesday, would cost at a time when Mr. Bush is under pressure because of a growing budget deficit. But White House officials have made clear that they do not want to cede the politically potent issue of health care to the Democratic presidential candidates, all of whom have made health care a...