There's a fun general-purposes discussion on the primary wind-down on Oregon Media Insiders - an open thread in which writers talk about the campaigns and especially their interaction with the media.
One standout point came from a commenter who, in an Oregon election window of three weeks between ballot mailout and election day deadline, disapproves of early voting: "voting before election day is ill-advised. . . . I wonder how many Republicans are now wishing they could change their vote in the Mannix-Erickson race, and how many more will wish they could if it becomes clear who's lying. Another problem with early voting is that it short-circuits campaigns that depend on voter education (these tend to be liberal/progressive in nature). In the past decade I've seen several good candidates/measures go down to a close defeat (and several bad ones eke out a close victory) despite polls showing a clear trend in the other direction in the last days of the campaign. Surely early voting played a role in at least some of these outcomes."
A point of interest, though we take the opposite view: If enough people vote early, last-minute gotchas - which often constitutes much of the really ugly stuff - tends to get short-circuited. Generally speaking, voters are better off without it. By the time the ballots go out, pretty much all of what you need to know (or at is, is useful) about a candidate is already out there. Spreading out the voting tends to reflect a broader view of who and what the candidates are about, rather than just one 11th-hour punch to which the other side has little chance to respond.
As negative as this primary has been in Oregon, it might have been moreso with one-day voting. And at least, there's been plenty of time for give and take, rather than just the give.