In this campaign video, former presidential candidate Gov. Tom VilsackThomas J. VilsackUSDA: Farm-to-school programs help schools serve healthier meals OVERNIGHT MONEY: House poised to pass debt-ceiling bill MORE (D-Iowa) endorsed Sen. Hillary Rodham Clinton (D-N.Y.) for the Democratic nomination Monday.

"Sen. Clinton, I am proud to support you in your effort to be ht next president of the United States," Vilsack said.

"Hillary Clinton has been tried and tested like no other candidate for president. She is prepared to run a tough race and to win that race," he added.

Vilsack also announced Monday that he would serve as co-chairman of Clinton's national campaign and that his wife, Christy, would be co-chairman of her Iowa campaign.