Dana Goldstein explains why Barack Obama won’t be able to just “declare victory” after tomorrow’s primaries.  I think she’s right — by the math and on the merits, he’s entitled to do so, but the backlash against an explicit effort to force Clinton out before she’s prepared to concede would be too big.

The backlash would be particularly great if he didn’t win either of the primaries and then declared the race over.  Clinton’s lead in Kentucky is so gaudy and embarrassingly large that his supporters have been reduced to talking about Oregon “cancelling” out a Kentucky loss, even though they are comparably important states in delegate count (52 vs. 51) and she stands to win by 25+ points while he might win by ten if he’s having a good night.  It’s very, very unlikely that he would lose both, but if the margins are anything like the four or five-point margins that we have been seeing in the most recent polls his Oregon victory will not appear to be that much of a victory.  It will definitely put his Portland mega-crowd into perspective, and in the very unlikely event of an Obama loss in Oregon the gigantic size of his Portland crowd will be rather grimly contrasted with his limited support throughout the rest of the state

Update: Okay, SUSA gives Obama a sizeable lead in Oregon, and his support outside of Portland is quite strong.

Second Update: Kaus notes late pro-Clinton movement.