Subsequently authorities went to the Cherry Creek Hotel to contact an associate of Gartrell's. But that man, identified as Shawn Robert Adolph, 33, who was wanted on numerous warrants, jumped out of a sixth floor hotel window. Law enforcement sources say Adolph broke an ankle in the fall and was captured moments later. Sources say he had a handcuff ring and was wearing a swastika, and is thought to have ties to white supremacist organizations.

A third man -- an associate of Gartrell and Adolph, Nathan Johnson, 32, was also arrested. He told authorities that the two men "planned to kill Barack Obama at his acceptance speech."

Johnson, along with his girlfriend, Natasha Gromek, are also under arrest on drug charges.

"We're aware of the matter discussed tonight by the Aurora Police Department," said Colorado U.S. Attorney Troy Eid in a statement late Monday night. "Federal law enforcement is working hand-in-glove with the Aurora Police Department. Because this matter is currently under investigation, there is little we can say right now.

"We can say this: We're absolutely confident there is no credible threat to the candidate, the Democratic National Convention, or the people of Colorado."