On my game I've been hoping for a democratic victory. I built the Aposollistic Palace and had the most votes of any of the nations. However when I built the United Nations I suddenly had a lot less votes than one of my rivals. Why is this?

For the AP only the votes of cities with your religion count. For the UN every city on the map counts. So the rival has no/few cities with your religion present, but for the UN vote all his population counts.

Palace has to do with religion. UN doesn't (think population counts).

Yah for the UN the entire population counts, however for the AP its the amount of the head religion.

The AP also only works on the continent it was built, so maybe the other country with a huge amount was continent so you didn't see them on the AP.

Another question regarding the Palace/Nations.

EVERYONE accepts global environmentalism except for a dinky little vassel who says refuse, and it fails, while exceeding the vote well over what it needed to.

I have seen many cases where a resolution will be "failed" while it is more than 100-300 points over what it needs to in order to succeed because a nation with very few votes says no (and not always refusal).

If one person refuses, the vote is automatically failed, but the civ that refuses gets -5 or -10(i forget which) happiness in all cities w/ the AP's religion, or in all cities w/ the UN

So is there any chance of me winning a democratic victory when my opponent's population is far greater?

It is possible but you need to be +10 to +15 with all of the rest of the civs since you and the largest civ will be up for the vote. If the other guy is significantly larger than it is not likely to happen since you and everyone else still aren't enough.

The AP also only works on the continent it was built, so maybe the other country with a huge amount was continent so you didn't see them on the AP.

You sure? This may appear to be the case normally since it is quite difficult to get a religion "across the pond" in sufficient numbers for it to make a meaningful difference in the elections but I am almost positive that AP benefits are global in nature and not related to sharing the same continent as the AP itself.

I assume you need to be the "resident" in order to achieve diplomatic victory and thus either you need:

1) to control the wonder; automatic candidate
2) have the largest "population"; automatic candidate
3) have the second largest "population" AND the person with the largest "population" controls the wonder (2 candidates required, and the owner qualifies for both automatic conditions)

Once you qualify under one of the three conditions you THEN need to get enough votes to get yourself elected and THEN get yourself voted the winner.

You sure? This may appear to be the case normally since it is quite difficult to get a religion "across the pond" in sufficient numbers for it to make a meaningful difference in the elections but I am almost positive that AP benefits are global in nature and not related to sharing the same continent as the AP itself.

Your right. The AP is global otherwise you couldn't get a religious victory on any map with multiple continents.