While it is conventional wisdom to state that Obama faces an uphill re-election battle against Romney and to be pessimistic in the Nate Silver sense about his chances, I believe there are number of reasons why Romney will prove to be a weak general election candidate and will never be President. It is Romney who has the daunting task.
1. The traditional Republican advantage on national security does not exist anymore. As long as he gives credit to the armed forces, Obama can and should ruthlessly exploit the deaths of bin Laden, Qadaffi, and others. If Mitt Romney wants to talk about returning to 1917 naval ship levels, he runs the risk of looking ridiculous. An increasingly likely Israeli attack on Iran, with the US getting dragged in, will probably result in a rallying around the Commander in Chief.
2. The Ryan Plan and Republican entitlement militancy can be turned against the Republicans with devastating effect among seniors, for whom Medicare is now a Third Rail. All the President has to do is quote the recent predictions of Grover Norquist. The Republicans aren't just reaching out to the Third Rail; they have put their scrotums on it.
3. Romney can make no credible criticism of Obama's biggest domestic achievement, the Affordable Healthcare Act and its mandate. Obama will cut him to pieces here.
4. The advocate of "Self-Deportation" and comrade of Kris Kobach cannot win any substantial fraction of Hispanics. He'll get even less than McCain, probably lucky to get 20%.
5. Romney cannot be in the position of wanting to preserve his own, preferentially low income tax rates when 70% of Americans think the rich should pay more. It is an impossible, ridiculous position for him, but Grover Norquist and the Club for Growth crazies will make sure he sticks with it.
Romney also faces further risks from the examinations of his taxes and business dealings which will continue. And, as Paul Krugman has said, Romney's actual implementation of his economic proposals would make everything much worse. Examination of his proposals outside the lunatic asylum of the Republican primaries will not help him.
All Romney has going for him is the ability to unleash a sewer of oligarch-funded SuperPac negativity. Against a President people basically respect as a person, this will have its limits for a man who is himself unlikeable and unliked.
It is going to be a turkey shoot.