While addressing differences, Clinton said Beijing and Washington have to "avoid unrealistic expectations that can be disappointed while holding firm on our values".
In the meantime, some former US politicians also called for a constructive attitude toward the visit.
The Washington Post published Henry Kissinger's article on "avoiding a US-China cold war", in which the 87-year-old former secretary of state proposed to "create a tradition of respect and cooperation".
Similarly, in the New York Times, former US national security adviser Zbigniew Brzezinski compared the importance of Hu's upcoming visit with former Chinese leader Deng Xiaoping's historic trip some 30 years ago.
Like many other observers, he stressed it is the mutual needs rather than differences that the two sides should focus on.
"Neither side should delude itself that it can avoid the harm caused by increased mutual antagonism; both should understand that a crisis in one country can hurt the other," the 82-year-old wrote.