The first baby boomers will be old enough to qualify for Medicare Jan. 1, and many fear the program's obituary will be written before their own. A new Associated Press-GfK poll finds that baby boomers believe by a ratio of 2-to-1 they won't be able to rely on the giant health insurance plan throughout their retirement. The boomers took a running dive into adolescence and went on to redefine work and family, but getting old is making them nervous. Now, 43% say they don't expect to be able to depend on Medicare forever, while only 20% think their Medicare is secure. The rest have mixed feelings. Yet the survey also shows a surprising willingness among adults of all ages to sacrifice to preserve Medicare benefits that most Americans say they deserve after years of paying taxes into the system at work.