(CNN) -- Sen. John McCain Thursday admitted his idea of a gas tax "holiday" would not solve the problem of rising oil prices but said it would give low-income Americans "just a little break this summer."

Sen. John McCain appears at a town hall meeting in Allentown, Pennsylvania, Wednesday.

"That's all this is about," the presumptive GOP nominee told CNN. "This is not the end of western civilization. This does not solve our dependence on foreign oil. It gives low-income Americans -- who drive further with older automobiles and are bearing the brunt of this -- a little bit of a break for the summer."

McCain, as well as Democratic presidential candidate Sen. Hillary Clinton, has called for a hiatus in the 18.4 cent-a-gallon federal gas tax between Memorial Day and Labor Day -- a period when vacationing Americans spend the most time on the road.

However, critics of the idea -- including Clinton's rival for the Democratic nomination, Sen. Barack Obama -- argue that a gas tax holiday would have limited impact on drivers' pocketbooks. Assuming the average gas tank holds 13 gallons, removing the gas tax would save drivers about $2.35 every time they filled their tanks, or, as Obama estimates, about $30 over the summer. Watch McCain push for a tax holiday »

A summer suspension of the gas tax would leave a funding gap of about $10 billion in the fund used to pay for federal highway construction, critics note.

But McCain argues the holiday would mean that drivers would "have a little money left over, maybe to buy a better meal, maybe to buy something for their kids."

"Maybe that is what this is all about," he said. Watch the candidates clash over gas prices »

In an interview with CNN, McCain also defended his proposal to offer families $5,000 in tax credits to help buy health insurance, saying it would not undermine the current system of employee-based health insurance, as Clinton has charged.

"I want to give the people a choice as to who they want to keep: their employer plan or go out with their $5,000 tax credit and go across state lines and around this country and get the insurance policy of their choice," McCain said. "Which ever they want to, it is based on choice." Watch McCain decry a government takeover of health care »

Experts have questioned whether the tax credit would help the roughly 47 million who are currently uninsured because the $5,000 is unlikely to cover the entire costs of a policy. The Kaiser Family Foundation says averages about $12,000 a year for a family of four.

But McCain said allowing more individuals to buy their own insurance would increase competition and lower costs and the tax credit is better than what is currently available.

"The $5,000 tax credit you are talking about will go to families right now who don't have any [insurance]," McCain said. E-mail to a friend

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