I think his greatest failure was not giving us a viable candidate in the V-P position. I love Cheney. But he should have bowed out second term and taken Chief of Staff position (use the health card). We needed a strong Veep to run and we did not have anyone. I would have run over people to vote Dick Cheney. McCain. Bah!! We flailed around during the primaries and beyond. Too bad.
Technically, I agree with what you are saying, but with the financial meltdown of 2008 and a big chunk of the public being weary of the wars in the mid-east, it would not have mattered who the Republican candidate was, they would have been toast in the general election. The political cycle has always ebbed and flowed like that, wise choices or not being made by the public. The only way I see that trend changing is with the demographic changes happening, the DNC is preparing to lock themselves into power for possibly generations and will do so successfully no matter how bad things get. The turd worlders pouring across our borders will vote Dem no matter how bad things get.