Preventive care in the sense I'm talking about means getting people to go to a normal doctor instead of a hospital for managable illnesses.
That has less to do with access to preventive care and more to do with increasing health awareness and treatment options for the general population (and access to non-hospital medical clinics in low income areas).
Health insurance already covers preventive treatments because it's cheaper than waiting for people to fall apart and leads to generally better quality of life/cheaper treatment. We want people to go in for checkups and generally be in touch with their doctor.
Leads to a better quality of life, yes. Cheaper in the long run (for the insurance company/taxpayers), no. To illustrate with numbers:
Say preventive treatment for Malady X costs $500 per person and Malady X itself costs $10,000 to treat. At the individual level, someone who would have gotten Malady X but didn't thanks to the treatment saves $9500. The problem is, and politicians like Obama don't mention, is that this is not applicable to large groups of people.
Say Malady X has a prevalence of 2% and the population that has insurance coverage is 100. Now it costs $50,000 in coverage to ensure that the entire population will be prevented from getting Malady X. However, if coverage only covers cost of treatment, then nobody is prevented from getting Malady X and 2 people will have it. Costs for treatment run at $20,000 total, which is significantly less than preventive treatments for everyone.
In actuality, the numbers are far more disproportionate than the ones I conjured up. Costs for preventive care for heart disease and diabetes run approximately 10 times higher than treatment costs. Note that this also assumes a 100% success rate for preventive care, which is very unlikely.
That said, you can't put a price tag on the people who are saved by access to preventive treatments...but as I said before, to claim it will also save money is just absurd and wrong.