It's tilt Republican but Democrats would be stupid to not try to knock off Burr. I think his horrific relations with veterans groups will hurt him in a state that has a lot of military bases.
They shouldn't give up on the race, but Burr is no longer a prime target.
Republican Seats up in 2016 (from most to least vulnerable):
1. IL
2. WI
3. PA
4. FL (Majority with Dem. President)
5. NH (Majority with Rep. President)
6. OH
7. NC
8. AZ
9. IN
10. MO
11. GA
12. KY
13. AK
14. LA (Filibuster-Proof Majority)
15. IA
16. UT
17. AR
18. SD
19. ND
20. SC
21. KS (Veto-Proof Majority)
22. AL
23. ID
24. OK