A KATU/SurveyUSA poll of some 600 likely voters—coming out just days before Tuesday's election—has fluoridation down 53 percent to 40 percent, with only eight percent over respondents listing themselves as undecided.

That's pretty much a worst-case scenario for fluoridation supporters, including the Mercury (our endorsement is here) and every other major newspaper in Portland. The same poll last week showed 14 percent of voters undecided, with 48 percent opposed and 39 percent in favor—implying that as people figure out how they want to vote, most are breaking toward the opposition.

CFV0516_08041624EC2.png

The phrasing of a poll question is always interesting. A bad question led a lot of people to write off the arts tax when polls showed it lagging—only to win with 62 percent of the vote. But in this case, it's impossible to blame the phrasing—which is pretty straight-up:

On the ballot measure concerning the fluoridation of Portland's drinking water supply, are you ... Certain to vote yes? Certain to vote no? Or not certain?

The crosstabs are filled with good tidbits. Fluoride is up big among "affluent" voters, but doing awfully among people who aren't and people who still have land lines. But here's an even more interesting detail, especially in a low-turnout election where every ballot actually in hand counts: Among respondents who said they already turned in ballots, fluoridation is losing BIG.

Screen_shot_2013-05-16_at_5.04.52_PM.png