Kitzhaber and Merkley have both become more popular over the second half of this year. Kitzhaber's approval rating is a +9 spread at 50/41. That's up 3 points from June when it was +6 at 45/39. Merkley's seen a more dramatic improvement in his standing. On our last poll he was at just a +3 approval spread (37/34) but now he's improved 12 points to +15 (44/29). Those are the best approval numbers we've found for him since he took office.
There are two Republicans who could be competitive with Kitzhaber and Merkley if they decided to mount 2014 campaigns: former Senator Gordon Smith and Congressman Greg Walden. Smith would trail Kitzhaber 47-42 and Merkley 47-43. That 4 point lead for Merkley over Smith is nearly identical to his 3 point win over him in 2008. Walden seems an incredibly unlikely candidate given his new leadership role but he would also come within single digits of both candidates, trailing Kitzhaber 49-40 and Merkley 47-42.