We know that the twitter community is pretty active all the time. So if you want to check whats hot on twitter and see trends related to different terms, then there is a nice tool called Twist , which is a part of the Flaptor real time twitter search engine.
Twist allows you put different terms separated by commas and then generates a chart showing the trends. So I decided to compare Obama and Hillary and check who is being talked about more, in twitter. Here’s what I got :-
Obama vs Hillary
You may also try Obama vs Hillary vs Mccain 
.
However, keep in mind that this may not conclude that Obama is more popular than Hillary on Twitter, because this only shows that twitter users are talking more about Obama ( And we know who’s more popular 
)
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