I think all three presidential candidates are wrong about the gas tax holiday simply because they don't understand how prices work. There will not be any $30 savings to consumers if you eliminate the gas tax. If anything, the price of gasoline will go up.
The fundamental role of economics is that demand will always exceed supply, therefore some people have to be dissuaded from buying and price is the ultimate dissuader. Therefore total price, the price the consumer actually sees, rises until enough consumers are dissuaded so that the remaining demand balances the supply available.
Total price is determined by that balance and if you lower the tax, or raise the tax, total price will stay the same. The price you see today is the price that balances the demand to the supply. However, removing the gas tax can make supply go down.
Normally, in the long run if the tax is removed, then more gasoline will be made available because suppliers' profits will receive more of the price. But at the present time, a lot of the supply is being held by speculators. If their profit increases when the gas tax is removed, these speculators are more likely to buy more gasoline.
Indeed, as long as the profit in hoarding gasoline increases then even MORE speculators will join the fun, just as we saw in the housing market, and a BUBBLE will raise gasoline prices even higher because they will remove more and more gasoline from the market and therefore total price has to rise in order to dissuade more consumers.
This is what makes the great irony: if you RAISE the gas tax during the summer then the total price seen by consumers will stay the same, but the profit to suppliers will be reduced. Since a lot of speculators work on leverage, an increase in the gas tax will result in some speculators being forced to release their hoarded supply. That temporary increase in supply will tend to deflate the current bubble and force a reduction in total price seen by consumers.
The only way total price changes is if the supply changes, not when any component of the price changes. The total price balances supply and demand. Since a large component of the current supply is being held in speculator's tank farms, anything that increases their profits will reduce the supply of gasoline because they will simply fill more tanks. It is only when the speculators find their profits declining that they will have to consider selling gasoline from those tanks, and this selling will be additional supply to consumers that brings down total price, albeit only while they are selling.
So the present debate over the gas tax holiday is a complete hoax. The only thing that reducing the gas tax will do is RAISE prices because speculators will take more gasoline off the market. The only thing that will LOWER prices temporarily is to raise the gas tax and force speculators to empty some of their tanks into the market.
Of course this is reality based, and only a few of us live their any more.