Replace:
sorted[sorted.length] = v[maxIndex];
v[maxIndex].score = 0;
with:
// ...
var clone = {};
for(var i in v[maxIndex])
clone[i] = v[maxIndex][i];
sorted[sorted.length] = clone;
v[maxIndex].score = 0;
// ...
Of course, you haven't stated how deep your objects are - I assume they are simple key:value
maps but this should be enough to steer you in the right direction.