America is definitely "Costco Country."

The giant retailer, which hawks merchandise at supposedly "near wholesale" prices, understands and exploits the fundamental mentality of the American consumer: Most do not, and often cannot, make a decision.

Costco's marketing research apparently validated that premise. On a table with a dozen brands of ketchup, all priced within a few cents of each other, consumers were asked to make a decision. More than half couldn't, and didn't make a purchase.

So Costco's marketing plan is simple: Sell only one brand, eliminating choice. Sell it ridiculously cheap, eliminating price resistance. Sell it in big lots, so consumers have to buy a vast quantity to realize "savings," and make a tidy profit.

So let's apply this premise to politics. On Nov. 6 voters must choose among 100 or more candidates, including retention for judges. If consumers can't choose a bottle of ketchup, how do voters pick a candidate?

The answer: At least 80 percent of the voters simply choose a brand name, Republican or Democrat. The reasons range from ancestral to habitual to prejudicial.

In Chicago, one is "born a Democrat," much as one is early socialized to be a Cubs or White Sox fan, and such allegiance is never questioned or renounced. For more than 90 percent of African Americans in the country, voting for a Republican is akin to racial treason. Hard-core conservatives (about 35 percent of the population) and hard-core liberals (about 25 percent) view politics as economic or social warfare and always vote Republican and Democrat, respectively.

Voting the party label is a no-brainer. One need not think, choose or justify.

Appealing to the remaining 20 percent is a bit trickier. These are the chronically undecided voters, the one-issue voters, the I'll-vote-if-I'm-not-too-busy voters. They want a candidate with a touch of class, with poise, charm and a sense of humor. Likeable and incorruptible. Not too opinionated, or argumentative, or controversial or overly cerebral. In short, the picture of perfection, but not condescending or arrogant. A nice person who's rich enough not to want to steal the store. They want the equivalent of every woman's dream of "Mr. Wonderful." Good luck.

Every serious candidate has a political pollster and a political consultant. The pollster tells the candidate what the public -- meaning the 20 percenters -- wants to hear. The consultant tells the candidate how to say it. Scripting every word and gesture is obligatory.

So how does the politician close the sale on the 20 percenters? The options are to go positive or to go negative.

First, there's the "comfort zone" offense. Think Rich Daley. Lots of warm and fuzzy commercials about what a great job he's done, how indispensable he is, how he loves his city. That combats voter fatigue with the incumbent, but it works only when the candidate is well known, reasonably well liked and passably competent, and has an it's-time-for-a-change opponent. It was especially effective for Daley when he had a black opponent.

Second, there's the "huge issue" offense, which is rare. Think the 2006 Stroger-Peraica race for Cook County Board president. After Todd Stroger was appointed to replace his ailing father, Tony Peraica ran a "no nepotism" campaign and got 47 percent of the vote. Generally, the differences between candidates are minimal: Nobody's for raising taxes or nuking the terrorists. Everybody's for "taxing the millionaires and billionaires" and for the "American dream."

Third, there's the "catchy slogan" -- and say as little as possible -- offense. Think of past presidential races: Woodrow Wilson in 1916 ("I have kept you out of war"), Dwight Eisenhower in 1952 ("I like Ike"), Richard Nixon in 1972 ("Four more years"), and Barack Obama in 2008 ("Change we need").

As Democratic consultant James Carville once said, campaigns are all about "KISS," which means keep it simple, stupid. If you can't plausibly enunciate a compelling reason for voting for you, then propound a multiplicity of reasons to vote against your opponent.

When voters enter the polling booth, they don't want to grapple with solving Einstein's theory of relativity. They want to briefly do their "civic duty" and get on with their lives. With a hundred choices, it's a lot easier to vote against somebody.

Which brings us to the epitome of modern campaigning: Negativity means electability. Go positive, but be bland and unspecific; go negative, and be inflammatory. Demonization works. It's much easier, and much less dangerous, to unsell your opponent than it is to sell yourself. Articulate a dozen specific stances and somebody will find fault; rip your opponent as an "extremist," or a "tax raiser" or "dishonest," and some of the 20 percenters will react favorably.

Think Dick Durbin and Rod Blagojevich. In 1996 Durbin, then an obscure Springfield congressman who had conveniently switched from anti-abortion to pro-abortion rights to run statewide, ripped his Republican opponent, Al Salvi, as an "extremist," particularly on the issue of gun control. Instead of selling himself, Durbin unsold Salvi, and he won by 655,204 votes.

The now-disgraced Blagojevich, who raised $25 million for his 2002 campaign and another $25 million for 2006, had his ads all over television blasting Judy Republican Baar Topinka with the line, "What was she thinking?" Topinka wanted to cut state spending, and the governor demonized her, winning by 367,416 votes, an increase from his 252,080-vote win in 2002. Blagojevich, with an uninspiring and insipid tenure, gave voters no reason to vote for him, but he gave the 20 percenters a vague but persuasive reason not to vote for Topinka. Blagojevich got 1,847,040 votes (52.2 percent of the total cast) in 2002 and 1,736,731 votes (49.8 percent) in 2006. Republican Jim Ryan got 1,594,960 votes (45.1 percent of the total) in 2002, and Topinka got 1,369,315 votes (39.3 percent) in 2006.

Here's a look at two 2012 contests, where untruths abound and negativity flourishes:

8th U.S. House District: Incumbent Republican Joe Walsh seems determined to bring Chernobyl, the site of the Russian nuclear facility meltdown, to the northwest suburbs. Walsh, a relentless campaigner who was making significant progress in his underdog campaign against Democrat Tammy Duckworth, is in a meltdown mode, and his toxicity, bordering on radioactivity, is now insurmountable.

Polling dating from mid-October showed him inching ahead -- an astonishing achievement in a newly created district in which Obama got 61 percent of the vote in 2008. Duckworth's campaign had been largely negative to that point, harping on Walsh's "extremism" and Tea Party voting record. Her positive ads were pablum, replete with such bromides as "standing up for Illinois." Her comment that "things are better now than 4 years ago" and her close ties to Obama gave Walsh an opening for attack, provided he stayed on the economic message and made the race a referendum on Obama's policies.

He didn't. At a recent debate he said that he's against abortion, with no exceptions -- not for rape or incest and not even to save the life of the mother. Then he tried to explain himself, mumbling about ectopic pregnancies. As such, he violated a cardinal political rule: Never explain and never apologize. If you do, you've lost.

Suddenly, Duckworth's television ads blasting Walsh's "extremism" have credibility. The hard-campaigning Walsh, who is viewed by his backers as gutsy and principled, now seems wacky. He has progressed on the political spectrum from conservative to extremist to crackpot. "Too extreme, with no exception," blare Duckworth's commercials, and a new ad barrage rips Walsh as a deadbeat, claiming he owed $117,000 in past child support, although the case was settled.

Conservative Super PACs seem much enamored with Walsh, and the Now or Never Super PAC reportedly will spend $4.3 million in anti-Duckworth television ads. Because she is demonizing Walsh, and now by demonizing Walsh's Super PAC backers, over whom he has no control and whom the media claim have pledged to "bury" Duckworth, money is flowing fast and furious into the Democrat's coffers. Obama will win the district 53-47, but the 20 percenters will now break for Duckworth by 60-40. Walsh will lose.

10th U.S. House District: Enough already. That's the attitude of the well read, upscale, disinformation-intolerant voters in the North Shore district, where Republican Bob Dold won by 4,651 votes in 2010.

Having been deluged with negative ads during the 2006, 2008 and 2010 campaigns, when the Democratic candidate was Dan Seals and Mark Kirk was the incumbent, voters in 2012 are in an irritable mood. Dold is no liberal, but Democrat Brad Schneider's attacks him as being a Tea Party congressman, for voting to defund Planned Parenthood, for favoring oil drilling in Lake Michigan, and for gutting Medicare due to his support for the Wyden-Ryan bill.

Those are lies. Voters know it, and they resent it. Dold has responded in kind, blasting the uncharismatic Schneider for alleged tax dodges and highlighting his quote that we "should borrow all day" to solve the fiscal mess.

Hell hath no fury like an independent voter insulted. Obama won the district with 62 percent of the vote in 2008, but Kirk was re-elected by 14,906 votes, meaning that one in five Obama voters opted for Kirk.

It will be deja vu in November. Many independent voters will make a statement by voting Obama-Dold. The Republican will be re-elected.