Blocking the only Black person's entry into the Senate makes them look bad and reminds everyone that Oh, Yeah, George Wallace and Orval Faubus were actually Pro-segregation Dem's and we can't let anyone know that it was really Dem's that were Anti-Civil Rights.
Diane MAYBE recognizes the need to have a real professional run CIA rather then Stansfield Turner v2.0. Having a major terrorist attack in the US anytime after 20 Jan will enable the R's to point out that "After 9/11 President Bush implemented policies that prevent any attacks, But since Obama has taken over, well look at the bones....."
Same reason Obama hasn't said anything about Gaza, he's about to shaft Israel.