I’m from New England, but I still think Oregon unless I have reason to believe otherwise. I guess just because it’s definitely the larger city.
It could have been worse. Portland, Ore. was named when two founders, Francis Pettygrove and A.J. Lovejoy, flipped a coin to see what moniker the new burg would take. Pettygrove’s hometown was Portland, Maine, and he won the flip. Lovejoy’s hometown was Boston, Mass… Now, imagine the confusion if we had two large cities called Boston, one East, one West.
Growing up in the heart of the midwest (Omaha), and then in the ass of the US (Arizona), I have always associated Portland with Oregon.
Hot, dry, skanky, dusty ass.
I think of Oregon, but then I live about an hour away from that Portland. Heck, I only know there is a Portland, Maine because my favorite band was playing there, and I was all excited before I realized it said Maine.
My default Portland is the one in Maine because it’s closer, and the brother in-law-bought a summer place near there last year (have to be nice to him now).
Occasionally on the SDMB I’ll see threads related to a Portland Dopefest. The first couple of times I saw it I thought “There are that many Dopers in Portland Maine?”.