He probably realizes that Republicans are going to look at it. And one of the justifications for killing it, is that you aren't conserving hardly any gasoline because mpg drops when you add the ethanol. And you probably are increasing green house gas emissions by the time you consider additional fertilizer and such.
So Gore is just doing the faux leader thing. Figure out where the crowd is going and get out in front of it.
Not to mention the vast amounts of water that is required to make just one gallon of ethanol.....