It's almost official. Portlanders will probably get to vote—yet again.. ugh...—on the wisdom of joining much of the rest of the United States in joining one front in the ongoing war against childhood tooth decay by adding fluoride to our municipal supply.

The city auditor's office says a referendum challenging the Portland City Council's unanimous approval of fluoridation is cleared to appear on the May 20, 2014, primary election ballot—unless the council decides, for whatever reason, that the expense of a special election, held before then, is worth the cost.

The referendum's success was all but certain after it was announced last week that only 3 percent of some 40,000 signatures turned in by fluoridation foes (they only needed nearly 20,000 good ones to qualify) were invalid. The city auditor's paperwork is here.

I wonder if the cost considered by city commissioners, as they decide whether to leave this for 2014 or not, will include politics. Dan Saltzman and Nick Fish will both appear on the ballot for re-election, should they choose to run again, and both came out as strong supporters. (Fish went so far as to announce his support well before a vote was scheduled.)

The push could bring out a bunch of voters who otherwise wouldn't cast ballots in those races, adding a little bit more spice to their campaigns. Then again, support for fluoride also was supposed to make a difference for Amanda Fritz, who faced the equally pro-fluoride Mary Nolan. But it didn't.

Meanwhile, the O reports that fluoride foes also are looking at a separate initiative that would ban any future city plans to add fluoride to Portland's water supply. I think I'm going to hide.