Michael Giuffrida writes "Google Trends is a free application produced by Google that shows how often a given keyword is searched for, over time. After seeing how candidates in the 2008 primaries have done in Google Trends in different states, it's clear that this tool can be very useful for campaigns." Read on below for some of the specifics about how these candidates have fared, Google-wise."For example, in New Hampshire, in the days leading up to the Jan. 8 primary, Clinton was searched for the most, followed by Obama, followed by Edwards — which was how the primary results turned out. In other words, the candidates most searched for on Google by users in New Hampshire were also the candidates with the most number of votes. This works for many other states as well.
For the first 37 Democratic primaries and caucuses, 32 states had enough data on Google to make a prediction. This method correctly predicted 27 of those 32 sates. Predictions aside, the tool is also useful simply in finding out how popular a candidate is in different states, assuming that the more popular candidates are entered more often as a search term in Google (an assumption that was verified, at least for the Democratic primaries, by the positive association found)."