Nested values in Javascript

var president = [];

for(k in votes) {
    president.push(votes[k]['president']);
}

After this, you need to count the occurrence of each element in the president array.

I worked this out. A little haphazard, but gives correct answer.

var votes = {
 "Alex": {president: "Bob"},
 "Bob": {president: "Mary"},
 "Cindy": {president: "Cindy"},
 "Devin": {president: "Louise"},
 "Ernest": {president: "Fred"},
 "Fred": {president: "Louise"},
 "Gail": {president: "Fred"},
 "Hermann": {president: "Ivy"},
 "Ivy": {president: "Louise"},
 "John": {president: "Louise"},
 "Kerry": {president: "Fred"},
 "Louise": {president: "Nate"}
  }
  var holder = {};
  var largest = 'Alex';
  for( var i in votes){
    var num = holder[votes[i].president] || 0;
    holder[votes[i].president] = 1 + num;
        if(holder[votes[largest].president] < holder[votes[i].president]){
            largest = votes[i].president;
        }
  }

  console.log(largest); // louise

You will have to make a list of every president and count in an array. As karthikr already mentioned in a comment

var presidents = {},
    president;
for(person in votes)
{
    president = votes[person].president;
    if (! (president in presidents))
        presidents[president] = [];
    presidents[president].push(person);
}

that will put every president in a list (presidents) with the people that voted for him.

to get the president with the highest ammount of votes is nothing more than iterating through the array and doing a check if this president has more votes than the current voted highest president.

var highest = false;
for(president in presidents)
{
    if (! highest || presidents[president].length > presidents[highest].length)
        highest = president;
}

That's a good start, now you'll have to code the loop to count the votes. Something like:

scores = {}; //will hold the names and votes.
for (i in votes)
{
     var votedfor = votes[i].president; // get who was voted for
     if(scores[votefor]) scores[votefor]++; //if we have the name in our scores, add 1
     else scores[votefor] = 1; //if we don't - set his(or her) score to 1 (which also add to scores).
};

Scores then holds {"Bob" : 1, "Fred" : 2, "Mary" : 1, "Louise" : 3 .... etc } Notice that it's unordered.

Something like this:

results = {}
for (voter in votes) {
    choice = votes[voter].president;
    if (!results[choice]) {
        results[choice] = 1 
    } else {
        results[choice]++
    }
}

Your best bet would be to do a map reduce using a framework like Backbone.js

Assuming you're doing this with no frameworks, you already have how to get who each person voted for. Why not store the totals in an array?

var voteTotals = [];
for (i in votes)
{
     // get who the current vote was for
     var currentVote = votes[i].president;
     // initialize to 0 votes if no votes found for this person yet
     if (!(currentVote in voteTotals)) voteTotals[currentVote] = 0;
     voteTotals[currentVote]++;
};

for (i in voteTotals)
{
    console.log(i + ": " + voteTotals[i]);
};

Then, you should be able to sort and get the values as needed!