U.S. Secretary of State Hillary Clinton urged American companies to sponsor the country's pavilion at next year's World Expo in Shanghai during her visit to the Expo site on November 16.

The main steel structure of the U.S. Pavilion was completed last month, three months after the world's largest economy confirmed its participation in the Expo following arduous fundraising efforts.

Construction of the structure was done in no time—it usually takes half a year to finish a 6,000-square-meter pavilion, one of the largest at the Shanghai Expo.

Delivering a speech in front of the U.S. Pavilion, Clinton, in her second visit to China as Secretary of State, is hoping more investors will contribute another $20 million to meet the $61 million budget of the pavilion.

"We were grateful for your generosity and steadfast belief in the importance of the Expo, in the American role here and what this U.S. pavilion can do to strengthen cooperation and partnership between the American people and the people of China," Clinton said.

The United States had in September raised about two thirds of the funds it needs, according to Jose Villarreal, U.S. Commissioner General of the U.S. Exhibition to the Shanghai Expo.

And Clinton wants more visitors, too.

"We are building it, and we believe when the Expo opens in 166 days, 70 million people will come. And with this rain today, maybe 100 million, and with that even greater good fortunes," she said.

According to U.S. laws, all funds for U.S. participation in the Expo should come from the private sector.

But companies are reluctant to dip into their pockets amid the economic crisis. At one point, some critics thought the United States may miss the Shanghai gala.