In a 90-7 vote, U.S. senators, including Mark Udall and Michael Bennet of Colorado, voted against a plan to spend $80 million to close Guantanamo Bay prison and possibly move the prisoners to the federal Supermax facility in Florence. That's according toÂ The Denver Post, which notes the vote is considered a blow to President Barack Obama's promise to shut the controversial prison that houses inmates swept up in the nation's war on terror. Before the vote, Udall and Bennet, both Democrats, clashed with Senate Intelligence Committee Chairwoman Dianne Feinstein's suggestion that the detainees be sent to Colorado, reportsÂ Politico. Both senators want to see Gitmo shut down, but raised concerns, including that Supermax is not a military facility. A Pentagon report obtained byÂ The New York Times, meanwhile, concludes that about one in seven of the 534 prisoners who were transferred abroad from Guantanamo returned to terrorist or militant activities.