Catholic questions, Kerry, Guilani and Pelosi?

If the Catholic church allows John Kerry, Rudy Guilani and Nancy Pelosi to take communion in their churches, why don't they allow Protestants to take communion? All of the above named people are 'good Catholics' but do NOT follow their church teachings on abortion issues, and divorce and re-marriage issues. What's then, to stop a Protestant who is visiting a Catholic m, from taking the Eucharist? Catholic doctrine denies these people the Eucharist, but it seems they continue to take it.