PIETERMARITZBURG, South Africa (CNN) -- Lawyers for Jacob Zuma, president of the African National Congress, urged judges Monday to declare Zuma's prosecution on corruption charges unlawful.
Jacob Zuma supporters at the Pietermaritzburg court.
Hundreds of his followers, who see him as the champion of the poor, gathered Monday outside the courthouse in Pietermaritzburg, wearing T-shirts and carrying placards of support for the man they want to be South Africa's next president.
Zuma contends the case against him amounts to political persecution -- not criminal prosecution. He says it's aimed at harming his chances to become his party's nominee to be South African president next spring.
Zuma could spend at least 15 years in jail if found guilty of accepting bribes from a company that won a contract for a multi-billion dollar arms deal.
He also faces charges of having a corrupt relationship with his former financial advisor Schabir Shaik, who is serving a 15-year sentence for soliciting bribes for Zuma and using Zuma's political influence to benefit his businesses. Watch more about Jacob Zuma's court case »
Shaik's conviction led President Thabo Mbeki to fire Zuma as his deputy, but it also energized Zuma's political base.
"And then the argument will be made that a sitting president cannot be liable, that they should not be liable for a trial or subjected to a trial because it will bring the country into disrepute," said political analyst Adam Habib.
If Zuma's lawyers fail to end the prosecution with Monday's arguments, they will get another chance in December, when the court hears other defense motions to derail the case.
Zuma , in a CNN interview, said he sees nothing inappropriate about running as the ANC's presidential candidate while still facing criminal charges.
"I can feel it's not appropriate if I know I'm guilty," Zuma said. "Why should I feel it's not appropriate when I'm not guilty?"
Habib said the case against Zuma is a test case for South Africa's democracy and the independence of its courts.
"Obviously, the strength of this case and how the courts act in this case and in other cases of a high-profile nature will either strengthen our institutions or weaken them," Habib said. "And let's hope they deal with it in a way that respects due process of the law that respects the rights of individuals but also respects the need for justice to be seen to be done."
Zuma lost a crucial round last week, when South Africa's Constitutional Court rejected his claim that a raid on his home was illegal; investigators seized thousands of documents in the raid.