What is the stochiometric equation of the sucrose and potassium chlorate reaction with sulfuric acid?
In this paper [Sugar Dehydration without Sulfuric Acid: No More Choking in the Classroom! T.P. Silverstein and Y. Zhang. J. Chem. Ed. 75 (6) 748-749 (1998)], the authors outline two reactions involving sucrose and sulfuric acid. The first one does not include $\ce{KClO3}$ and utilizes a significant amount of $\ce{H2SO4}$ in order to fuel the dehydration of sucrose: this is not the reaction you're interested in.

The second reaction detailed herein makes use of a very small amount of sulfuric acid to start the reaction (a drop is the commonly-cited amount): the sucrose is oxidized by $\ce{KClO3}$. This is the reaction you want to examine.

The authors give the reaction stoichiometry as
$$\ce{C12H22O11(s) + 8KClO3(s) \xrightarrow{H2SO4} 12CO2(g) + 11H2O(l) + 8KCl(s) + heat}$$ 

They note that the fumes from the reaction contain $\ce{Cl2, ClO}$, and $\ce{ClO2}$, but the amounts are not quantified. I suspect (but don't know for sure) that the amounts are finite but negligible. And even with the scant amount of sulfuric acid used here, I think you're safe going with the reaction as presented above.