Two things are worth noting. First, utility costs are a bigger problem than gasoline. On a percentage basis, the poor pay 7x as much for utilities as the well off, while they pay only 4x as much for gasoline. What’s more, unlike gasoline, there are seldom any reasonable alternatives for utility expenditures.
Second, there are always tradeoffs. Using the money from permit auctions (or carbon taxes) to rebate other taxes is indeed progressive if the rebate is fairly flat, but only if you pay taxes in the first place — which many of the poor don’t. For the very poorest, then, a tax rebate scheme would still be regressive: you’d essentially be hitting them with a big new energy tax without any offset at all. Conversely, a more targeted approach, like expanding funding for the Low Income Home Energy Assistance Program, helps the poor more directly but removes the incentive to use less energy.
The answer, then, is almost certainly a bit of this and a bit of that. No single solution targets assistance to the poor ideally, but a basket of solutions (payroll tax rebates, energy assistance, more funding for mass transit, etc.) can do a pretty good job. It won’t be perfect, but a well-designed program can make a cap-and-trade program pretty progressive.