I find it hard to argue against the thesis in this article. Both political parties have been pulled to right. Its really about how far to the right will be go under both candidates. Romney put Paul Ryan on his ticket to cut spending on social programs in order to pay for tax cuts for his friends. Obama decided not the let the Bush tax cuts expire and his healthcare bill was modeled after Romney's plan in Massachusetts that was designed by the conservative Heritage Foundation. It was better than nothing but the GOP succeeded in convincing many American's that it was a socialist plan. Many American's were especially unhappy about extending healthcare benefits to the poor ( which is a euphemism for minorities to many in the South).
Part of the pull to the right is due to the role of money in our political process. Both political parties have to compete for funds in order run effective campaigns. Few of the fund providers want a more progressive tax system, or government spending on programs that do end up putting money in their pockets. If Obama wins the election and does not have to worry about raising money for the next election he might decide to attack our corrupt funding system. That would be popular with a great majority of Americans. That might also be the reason why the far right would rather not have a president elected who is not dependent upon raising money for the next election. In any case, our political system is further to the right than most Americans really want it to be. It has been pushed there by money and most American's are aware of it.