Mitt Romney says they're "job creators" and vows to come to their aid as president. Newt Gingrich visited them on his "jobs and growth" bus tour. President Obama calls them "the engine of our economy."
If there's one thing Republicans and Democrats agree on, it's that small business is the answer to what ails the economy. On these tiny bundles of entrepreneurial energy, they say, rides the nation's hope for lower unemployment and faster economic growth.
But the work of several economists suggests that most small businesses are not particularly adept at creating jobs, at least not the best jobs. The work also suggests their role in generating national wealth has been exaggerated.
The problem is that not all small businesses are created equal. Businesses just getting off the ground contribute most of the country's job growth, but older small businesses cut as many as they add.
Think Bill Gates and Paul Allen huddled together late nights developing Microsoft, not the corner liquor store.
"I don't want to pick on dry cleaners and restaurants and small manufacturing firms, but they're not a big source of job creation," says John Haltiwanger, an economist at the University of Maryland.
Politicians like to say that small companies create two of every three jobs in a given year. That's less impressive when you consider that almost all the 6 million companies in the U.S. -- 99.9 percent of them -- are small businesses, with fewer than 500 workers.
What's more, two-out-of-three masks the fact that most small businesses eliminate more jobs than they create in a given year, either through layoffs, closings or bankruptcy.
And many of the rest, the ones that don't shrink or shut down, don't offer much hope for the millions of Americans looking for jobs.
Many small companies -- outfits like florists, hardware stores and barbershops -- tend to grow with the U.S. population, not faster. So they don't speed the economic recovery the way an exploding new industry might.
According to an August study by two University of Chicago economists, most small business owners just want to be their own boss and never expect to hire more than a few employees.
In fact, the more you study the numbers, the more you wonder what the politicians are getting so excited about.
Haltiwanger and two other economists showed, in a study of millions of companies over 30 years, that small businesses no more than 5 years old -- that's about 40 percent of them -- are the only ones that create more jobs each year than they cut.
By contrast, big businesses, the ones that get all the headlines for layoffs, have hired more than they have cut -- about 0.1 percent in a typical year.
Economist Charles Kenny of the New America Foundation, a nonpartisan research group, goes as far as suggesting that Washington should stop offering certain incentives to small business owners, such as loan guarantees and write-offs on taxes for home offices. He says the money would be better spent subsidizing research and development.
"If you want jobs, you have to focus on the innovative firms trying to provide something new and different," he says.
The country's unemployment rate is 8.3 percent, the lowest in three years. But the U.S. still has 5.6 million fewer jobs than before the recession. Assuming the pace of hiring from last year continues, it will take three years to recover all the lost jobs.
Small businesses aren't helping much. They cut more workers than they hired in all but three months last year, and contributed zero to job gains again in January, according to a survey by the National Federal of Independent Business.