Oregon is one of the last states that would have a problem with Obama's shift on marriage equality.
http://www.uselectionatlas.org/RESULTS/state.php?fips=41&year=2004&f=0&off=60&elect=0
Granted, that was back in 2004, and it's even possible that a narrow majority now supports it in OR. But it's also a safe bet to say that gay marriage is less popular than the Democratic Party in Oregon (ditto for every other state, probably), and therefore Obama's shift is going to be a net negative for him there.
2004 is a lifetime ago in politics, there have been a lot of big shifts since then. Bush didn't even win the state with that result on marriage equality and it likely wasn't the reason he even got close.
This. In 2004, people nationally were against gay marriage 60-30. Things have changed quite a bit since then.
