Sometimes it helps to use a little diplomacy. It depends on how the other players approach the game.
If someone has a hot head, try to instigate a fight between them and someone else. Once one big fight breaks out in a stalemated game, it usually doesn't take long for someone else to take advantage of the situation. Also watch for any non-members in the game, since they only have a 4 game limit they're not likely to want to stick around in a stalemated game. You might be able to nudge them into starting a war with someone (other than you!).
I've got an existing game (Game 10123176
), that just went past the 1 year mark this month. Its an 8 player World 2.1, foggy, no spoils game. Its down to 3 of us with no end in sight. I've been the game leader for a while, but our troop levels are so high I doubt I have much of an advantage. To be honest, I'm not sure where to go with this one... There have been a few times (once just a couple turns ago), where 2 of us have come close to going total war - just hasn't happened yet.
Most stalemated games that I've played, we've either decided to play another escalating tie-breaker game, or someone ends up suiciding, setting off chaos. Best bet is try to stay on people's friendly sides so they don't suicide on you.