Elected office has become a protected family business in the Bronx: Next week, dueling father-and-son teams will be going head to head in a special election for the Kingsbridge City Council seat.

No sooner had term limited City Councilman Jose Rivera scrambled into a vacant Assembly seat last November than the borough’s Democratic machine rushed to fill his former slot.

They didn’t look far. The man they picked to run for the job was Rivera’s son, 22-year-old Joel Rivera. This younger Rivera, a junior at Fordham University, may have a rather anemic resume. But that hardly seems to matter: Bronx’s Democratic capo Roberto Ramirez is backing him–which has apparently won him some union support as well.

No way, Jose, say the father-and-son team of City Councilman Pedro G. Espada and State Senator Pedro Espada, Jr., who are backing Edwin O. Ortiz, Jr., a 35-year-old director of the non-profit Youth Against Drugs and Alcohol. Ortiz also says he has picked up personal endorsements from Bronx Congressman Eliot Engel and the Rev. Al Sharpton.

But even though Ramirez has long been able to hand-pick the candidates that he wants, close observers of this race say the election could swing either way. First, the registered voter roll in this council district is only about 3,000, making the margin of victory tiny. Historically, this district has one of the lowest voter turnout rates in the city. On top of that, special elections have notoriously low participation rates.

What that adds up to: Each candidate will be looking to get only 1,500 to 1,800 votes to win. “A bad-weather day could change the race,” one observer says. “In the end it will come down to who can get the voters to the polling booth.”

The second reason that the race is tough to call is that area politicians and political foot soldiers haven’t exactly jumped at Ramirez’s orders to publicly back Rivera. They are content to watch from the bleachers. Perhaps it’s the stench of failure around Ramirez after all four candidates he supported in last November’s major primaries lost elections.