Far be it from us to compare unsuccessful political candidates to an agricultural byproduct that's inedible by humans, but the wheat has been separated from the chaff in local and state politics.

Voters now can concentrate on two finalists in each contested race, and they've got three months to select their wheat in each race. As usual, The Columbian recommends extensive research from multiple sources on all candidates. That's the best way for an informed electorate to select the best public servants.

As the dust settles on last week's primary, here are several preliminary observations about the political landscape leading up to Nov. 6:

Much of the attention in Clark County is focused on the two races for county commissioner, and rightfully so. But don't forget a fiercely competitive and highly consequential showdown going on in the 17th Legislative District. This battle could help determine majority rule in the state Senate.

Sen. Don Benton is boasting a first-place showing in the primary, and the Republican incumbent has four terms sustaining his name recognition. Democratic challenger Tim Probst is boasting a bit of momentum in his career as well. In 2008, Probst's percentage of votes in a state representative's race improved from 48.1 in the primary to a winning 55.7 in the general election. In 2010, that percentage rose from 46.9 in the summer to a winning 53.0 in the fall. Probst hopes he can do the same this year after grabbing 48.7 percent of the votes in the primary.

Whether you support or oppose term limits, last week provided a way to strengthen your argument. In local legislative races (the three districts that do not cross county lines), all four incumbent candidates not only won but led the voting in their respective races. Those who advocate term limits can argue that the power of the incumbency is too overwhelming and, thus, should be constrained.

On the other hand, in those same districts, five legislative positions are open races, and a newcomer will be going to Olympia in each case. Those who oppose term limits can argue that there's plenty of churn anyway, so why worry? It helps to remember, though: five is an uncommonly high number in this case, just as four open races for statewide executive offices this year is an unusually high number.

The Herald of Everett poses a good question: In the primary, why are we even voting when there are only two candidates, or in unopposed races? That's a question the Legislature ought to ponder. All of those candidates advance to the general election anyway; it seems like a waste of time.

One possible answer: Granted, these might be unnecessary races, but politicians love the exposure. And guess who's responsible for changing this rule? You got it. Politicians.

Here's an interesting side note that has every political observer bamboozled. Rob Hill -- a relatively obscure gubernatorial candidate running on a single-issue platform (a $10 per pack cigarette tax) -- gained just 3.7 percent of votes statewide. No surprise there. But look what Hill did in lower Columbia River counties: He pulled in 15.9 percent in Cowlitz, 14.3 in Skamania, 11.8 in Klickitat, 11.6 in Wahkiakum, 11.1 in Clark, and 7.1 in Pacific.

We contacted several longtime curb-sitters at political parades, and they have no idea how this happened. Even Hill -- who says has no connections to Southwest Washington -- cannot explain it. If you can solve this mystery, feel free to add a comment online or call the editorial page department at 360-735-4564.