I'll offer a few scenarios which will all turn out to be wrong:
1. The protests lose momentum spontaneously.
2. The Chinese government backs down and allows open elections in 2017.
3. The Chinese government does a repeat of the 1989 crackdown.
4. The Chinese government backs down slightly but undertakes a shadow campaign against the leaders of the protest and gradually tightens rules on assembly and free speech. Nobody remembers anything by 2017 and only approved candidates run in an election that no one cares is rigged.