Formula on delegates may muddy the field in California primary

California's Democratic presidential primary may be the most crucial piece of Illinois Sen. Barack Obama's presidential hopes.

Thanks to party rules, he could receive fewer votes than New York Sen. Hillary Rodham Clinton but garner as many delegates — or more.

Of 370 delegates at stake, 241 will be divided among 53 congressional districts and allocated based on the vote candidates receive.

But not all congressional districts are equal. Some have as few as three delegates, some up to six. The amount depends on how heavily Democratic the district is.

As a result, a candidate who wins big in one district could receive fewer delegates than a candidate who wins narrowly in another.

For example, in a district with four delegates, a candidate with 62 percent of the vote would win two delegates — the same number as a candidate with 38 percent of the vote. But in a district with three delegates, a candidate who wins 51 percent of the vote would receive two delegates while a second-place finisher with 49 percent of the vote would get one.

In practical terms, districts with three or five delegates offer candidates a shot at a bonus: the chance to pick up an extra delegate with a low margin of victory.

"There's some real kinky math in it," said Bill Carrick, a veteran political consultant. "The end result is that even if you lose in a two-candidate race, you can get an even split in delegates. And the winner can pick up the extra delegate in the odd-numbered districts."