Question about Roman victory conditions

I ask because this is my first game and I want to make sure I can win so I can play all the other factions. I'm playing as the Julii and have conquered about 35 provinces or so. I can now attack the Senate and the other factions. My question is, do I have to completely defeat all other Roman factions (Senate, Brutii, Scipii) or can I just take Rome and 15 other provinces to win? I'm pretty sure I can take Rome and 15 more provinces, but totally defeating both the Brutii and the Scipii might be a bit harder, and I'd have to prepare a lot more.

Thanks!

Once you take Rome you meet one of the victory conditions - Become Imperator.
After that it's just a matter of hitting that magic number of 50 (not sure what happens of you lose Rome).

Thanks a lot, that really helps!