What convinced more people to come out and vote for Obama? The same method that could motivate more people to buy from you. This approach is already pushing more:

o Hikers to stay on marked trails.

o Hotel guests to use fewer towels.

o Homeowners to reduce their energy use.

(By giving you these examples, I was using the method to convince you that this must be a useful method if used in so many different ways.)

To encourage more supporters to vote, the Obama campaign brought in behavioral scientists to craft the message that has been echoed in recent days: “Record turnout expected.” They were evoking social proof.

Simply put, social proof means that we are more likely to do what we think many others are doing. Robert Cialdini described this effect in his popular book Influence as did others, including Cass Sunstein (now working for Obama) and Richard Thaler in Nudge.

Similarly, an anti-literacy campaign is highly successful because it evoked our collective pride, with the slogan “Don’t mess with Texas.”

The effect of social proof is stronger in times of uncertainty (people are unsure and/or the situation is ambiguous) or similarity (we are more likely to follow people who are like us).

You see variations of the social proof effect every day:

o You choose the busy restaurant instead of the almost empty one. You are drawn to crowded booths at a trade show or expo.

o After a murder/suicide is reported, head-on car collisions and plane crashes immediately increase.

o Fewer people are now smoking in the US, as it is out of fashion, except in groups where it is still popular.

o For twenty minutes a day, children who were afraid of dogs stood in front of a child who was happily playing with a dog. After just four days, 67 percent of them climbed into a playpen with a dog and played with it. Shy children can also be helped.

o If several people around you are overweight, you are more likely to gain weight.

o Bartenders sometimes “out” the tip jar for customers to deposit money into.

o Desperate Housewives invade the men’s room at a Springsteen concert, after the former bravely entered.

Brain imaging shows that when we think we’re out of step with our partners, the part of our brain that registers pain goes into overdrive, according to Cialdini. The herd instinct is strong.

Social proof happens when a business attracts more customers because, unlike the competition, it displays testimonials. When you see this woman looking at one of the two men, you assume that he is more attractive and important than the other man, simply because of where she is looking. Therefore, display your product near popular and non-competing products or other objects.

Using social proof in small, even inexpensive ways has a huge effect. For example, Positive Energy, a company where Cialdini is chief scientific officer, is invoking social proof to get homeowners to voluntarily reduce their energy use. Along with their utility bill, they receive a note praising them, “with a row of smiling faces (You used 58 percent less electricity than your neighbors this month!) from your neighbors over the last 12 months, and it cost you $741 extra).”

That caused a 2 percent decrease in energy use when tested in Sacramento with just 35,000 homes. That’s the same as taking 700 homes off the grid. Next social proof move? Reduction of water consumption.

Such peer or neighbor pressure, especially with consequences, is a powerful way to change behavior, as stickK is demonstrating.

Conformity, competition, even shame, are powerful motivators when social proof is evoked. For example, an Oregon county public campaign for homeowners to cheaply weatherize their homes met with little response. However, when churches, citizen groups and Girl Scouts were recruited for a door-to-door drive, 85% of the county signed up. (Which credible partners can you involve in a campaign based on social proof?)

If you want people to buy from you, provide as many ways and places (website, brochure, conversation, articles, etc.) for them to hear or read about the ones they already have. This type of social proof evokes the power of Previous Previous. The more your customers or customers’ situations or reasons for buying remind prospective buyers of themselves and their situation, the stronger their impulse to buy will be. Girl Scout parents, for example, were struck by the need to weatherize their homes.

What worthy organization can benefit from aligning with your business to evoke social proof?

This is how the Toluma firefighters obtained a much-needed but expensive piece of equipment, a deluge gun, without asking their cash-strapped city council for a penny. Business was slow throughout his city. Firefighters got nowhere when they asked business owners experiencing a weak economy for donations.

They reached out to the manager of the locally owned MyPizzaria to request a donation. Instead, the manager devised a way to evoke social proof to attract donations, to their mutual benefit. “Here’s what I can do. We can pick a Wednesday, say four weeks from now, to declare as ‘Saving a local life’. Eat firefighting pizza at MyPizzeria.” It is usually a quiet night. I make $500 or so. That day, after we sell $500 worth, every dollar after that I’ll split 80/20 with you – your cause gets 80% So if you inspire enough people to buy a pizza that day, you can raise more money than we you just asked me.”

The firefighters loved the challenge, and had downtime to participate. They had banners, signs, and ads printed for free by the local copy shop with a bright red “donated by” credit line. They asked local supermarkets and gas stations to display them. After the first posters appeared, the local association of realtors decided that this was a grassroots campaign (social proof). As avid networkers and experts, real estate agents volunteered to help spread the word.

In commute hours, two fire trucks, draped with banners, had firefighters and realtors waving on the busiest street. Then the growing army of volunteers visited complex offices, even those with “No Solicitation” signs. (Who’s going to kick out the firefighters?) Now, more patrons visited apartment complexes, video rental stores and schools. They put flyers and signs everywhere. Once people heard about her community’s cause, handing out flyers was like giving out candy. The local radio station, newspaper, and various bloggers covered the unfolding story.

When Wednesday finally arrived, the place was packed with lively people. Some were served at tables in the parking lot, thus attracting passersby (another sign of social proof at work). They made enough money to get the deluge gun. Most importantly it was fun and a win for all involved. Done right, social proof-based campaigns can draw a crowd so that more gets done with less work on everyone’s part.

Furthermore, this social proof-based partnership allows all parties to utilize their best talents and resources. Acting together for mutual benefit leads to deeper and more diverse friendships. Because they experienced the leverage power of the partnership, the participants are more likely to want to work together again.