Help! Diplomatic advise needed!

Ok, I've taken over my whole continent and I'm going for a diplomatic victory. Problem is that Greece is in the game, and I am barely keeping up with city-state control.

Then Greece DoWs me, creating 2 factions of city-states: his and mine. I am also at war with the Inca, but I vaporized their invasion force pretty quickly. I am under control of 7 city-states and he has the remainding 8.

First off, how many votes will I need to win a diplomatic victory?

Second off, should I continue the Cold War or do I need to show some aggression? I haven't researched many military techs since I am beelining globalization. Everyone else has completed the Apollo program except for me.

I don't want to lose this game simply because I get beat by a science victory when I should be able to win a diplomatic victory.

Oh, and there's only 3 civs left in the game.
EDIT: 4

Kill everyone...

Want to win diplomatic victory....

Go nuts and kill everyone. Alex and racist Pacha won't be missed

Do I even have enough time? They have already built boosters, and I'm behind in military techs

The Victory screen/menu should tell you how many votes you need.

Build the U.N., that gives you an extra vote.

Either:

1. Take out the remaining major Civs
2. Declare peace with Alex and steal his allied city states
3. Eliminate enough of Alex's allied city states so that you will win a diplomatic victory with your allied city states

How many cities does greece have? And who has the stronger military? Technically, concentrated your military, and start taking out greece. Also, just try winning the CS. Do you have lots of units? Maybe gift them?

Focus on killing the CS allies of Greece. They are weaker anyway. That will reduce his votes.

Thanks, guys!
It turns out that Greece declared peace one turn later, and let's just say that he gave me a loan one turn before the vote.

Great! did you win yet?