As more details are emerging about Tamerlan Tsarnaev's five-and-a-half month trip to Dagestan in 2011—a trip the FBI is being faulted for not following up on—Senator Lindsey Graham is saying that what tripped up the FBI was that Tsarnaev's name was misspelled on flight records. Graham says his source is an assistant director at the FBI, although the FBI's version of events doesn't mention the name with a typo in it.