New York City Mayor Michael Bloomberg doesn’t buy Census figures that show the population of Queens increased by just 1,300 over the past decade. Miami leaders say there’s no way the city’s population has increased by only 10 percent. And Santa Ana, Calif., Mayor Miguel Pulido says his city is growing -- not shrinking, as Census figures suggest. So begins a decennial tradition, as local leaders across the country make the case to Washington that their cities and counties are larger than the new figures indicate. In June, these cities and dozens more began formally challenging the Census numbers.

But these challenges aren’t likely to offer much relief. Take the case of Houston, which has a population just shy of 2.1 million, according to the Census. City officials believe Houston may have been undercounted by 100,000 people -- most of which are low-income immigrants living in rental housing. But even if Houston’s lucky, the Census will only increase its population by 1,000. Why the disparity? The Census won’t consider a locality’s challenge unless it fits one of three very specific, very technical types of arguments, such as the way housing is coded or how the boundaries of a jurisdiction are interpreted. As a result, Houston officials are searching foot-by-foot through maps of the city’s borders to make its case that the Census mistakenly counted as many as 1,000 residents as living outside its borders. What about the other 99,000? “We don’t think we’re going to be able to do anything about that,” says Margaret Wallace, assistant director for the city’s planning and development department.

After the 2000 Census, for example, undercount challenges increased the U.S. population by a mere 2,700 residents. The only other option for localities is to sue. But those cases are expensive and unlikely to garner results, since it’s almost impossible to determine the accuracy of a Census snapshot months or years after the fact. Localities may have better luck persuading the Census to tweak the official population estimates it releases in the years between decennial counts.

Still, at a time when governments are suffering from decreased revenue, cities may be willing to put up a fight, even if they’ll only see slight gains. Census figures dictate how the feds distribute more than $400 billion in funding to state, local and tribal governments each year. A 1999 study by the U.S. Conference of Mayors estimated that undercounts would cost cities $2,263 per missing person in the upcoming decade (the figure hasn’t been updated). In some cases, the results can be even more drastic. In Detroit, the latest Census count puts the city’s population below 750,000. That matters, because under Michigan law, cities with populations of more than 750,000 have special taxing authority. The change could cost the city millions, says Mayor Dave Bing.

“One change in one city can result in a .001 percent change for the entire country,” says Alyssa Lee, president and CEO of Social Compact, a nonprofit that works with cities to compile data for Census appeals. “But it’s huge for that particular location.”