(CNN) -- A tax credit to help individuals and families buy health insurance is at the heart of a health care proposal Sen. John McCain unveiled Tuesday.
The credits will spark greater competition among insurance providers and put "individuals and families back in charge," the presumptive Republican presidential nominee said during a speech in Tampa, Florida.
"Millions of Americans would be making their own health care choices again," McCain said. "Insurance companies could no longer take your business for granted, offering narrow plans with escalating costs."
Under McCain's heath care plan, individuals would be eligible for a $2,500 credit and families a $5,000 credit to help pay for health insurance if they do not subscribe to, or do not have access to, employer-provided health care coverage. The government would send the money directly to insurers.
McCain's plan would cost $3.6 trillion over 10 years, the campaign said. McCain would pay for the program by eliminating the tax break employers get for offering insurance.
Doug Holtz-Eakin, a McCain senior policy adviser, said the tax credit would allow individuals to obtain health coverage "tailored to the circumstances of your life" rather than being forced to accept the insurance provided by an employer. Watch McCain reject universal coverage »
McCain also proposed that state governments set up a nonprofit Guaranteed Access Plan to provide coverage to individuals who are denied coverage from private insurers because of pre-existing conditions. McCain said he would work with Congress, governors and private industry to adequately fund the program. Watch McCain say he wants a system accessible to everyone »
Holtz-Eakin said McCain's willingness to work with the states to create individual programs in each state shows he understands a "better job doesn't take the form of a one-size-fits-all plan formed in Washington."
McCain argues that the increased competition will lower health care costs, which will allow more of the roughly 47 million Americans who are uninsured into the system.
The Arizona Republican would also permit generic drugs to be imported from Canada to increase competition among pharmaceutical manufacturers.
"We know competition and choice drive down costs," said Carly Fiorina, a former Hewlett-Packard CEO who is advising the McCain campaign.
Holtz-Eakin said the plan would also encourage insurers and health care providers to deliver better health and disease management as well as more preventive medicine such as anti-smoking programs, which he said would further reduce costs.
Health providers would be paid for "doing the right thing" rather than being paid for every test and procedure, he said.
In coordination with McCain's speech, his campaign released a television ad that touts the plan. In the ad, which is airing in Iowa, McCain says, "I can characterize my approach on health care by choice and competition, affordability and availability. ... The fundamental problem is not the quality of health care; it's the cost of health care. So, health care must be made affordable and available." Watch McCain call for putting families in control »
Critics of McCain's plan said the tax credits would not put a significant dent into what a family must pay to buy health insurance on their own. The average cost of providing health care for a family of four annually is more than $12,000, according to the Kaiser Family Foundation.
For individuals with pre-existing conditions, the costs of obtaining insurance could even be higher, critics said.
Critics also said encouraging individuals to buy health insurance could undermine the system of employee-based health insurance, with no guarantee a new system would emerge to replace it.
Clinton picked up that argument while criticizing McCain, saying in a statement, "John McCain is proposing a radical plan that would mean millions of Americans would lose their job-based coverage."
"So while people might have a 'choice' of getting such coverage, employers would have no incentive to provide it," she said.
Fiorina, however, said McCain's plan would not undermine the employee-based health insurance system because employers would continue to offer health coverage to attract and keep quality employees.
McCain's free market approach to health care reform is very different from the proposals offered by the Democratic presidential candidates, Sens. Barack Obama and Hillary Clinton. Both of their proposals include more government mandates for health care coverage.
Clinton would mandate that every individual have health care and would provide government subsidies to those who could not afford to purchase insurance on on their own.
She would also allow individuals to join the private health care plans that are offered to members of Congress, and she would create a new public insurance program modeled after Medicare.
Clinton also includes tax credits to individuals to help buy health insurance and would require large businesses to provide or help pay for health insurance for their employees. Watch McCain says he opposes mandates »
Clinton's plan is estimated to cost $110 billion annually, which would be paid for by eliminating the Bush tax cuts for those making more than $250,000 and by eliminating waste and inefficiencies within the system.
Unlike Clinton, Obama would not mandate that every individual have health care insurance, but he would require health insurance for children.
As part of his plan, Obama would create a public insurance program for those not covered by private insurance and would also require large employers to help pay for their employees' health coverage.
Obama's plan is estimated to cost between $50 billion and $65 billion and, like Clinton's plan, would be paid for by eliminating the Bush tax cuts for those earning more than $250,000 a year. E-mail to a friend
CNN's Caleb Hellerman contributed to this report.