I think he's just a liberal who wants to be president. His goal in life is to wield power and further liberal causes.
Obama is different from him and every other liberal we have yet to have as president. He may be an ultra-liberal, but I'm not so sure. His liberal policies may very well just be a means to the goal of destroying America. He could also be a Muslim and an aspiring totalitarian dictator. I don't have those concerns about Romney, nor do I expect him to do things like aid Iran in the acquisition of nuclear weapons, incite race riots, intentionally crash the economy, or set up his own civilian police force as powerful as the military. Those are all possibilities with Obama.
Both Romney and Obama end up in the same place. They just take different roads to get there.
I don't know what precisely you mean, but here's where I think we end up with both. The United States, in many ways, came to an end in the 1960's (you're one of the few people here who see the big picture and recognize that. That's why I'm taking the time to give you my opinion like this.) Obama's second term will be the coup de grace. If Romney wins the election, America will continue to decline, but its coup de grace will be delayed. This extra time may allow a restoration of America, however unlikely it is.
As to your point, which was not necessarily raised on this thread, about the GOP resisting Obama, but not resisting Romney: its "resistance" to Obama so far should elicit no confidence that it will provide any meaningful resistance to Obama in his second term.
As to your point about not wanting Republicans to get the blame for the collapse of America: why do you care? We both dislike the GOP-e now. So, isn't it more logical to say "to Hell with the GOP" and not care whether it gets blamed or not?