Here is a link to an article that was passed to me by my father from the Miami Herald.
While Chavez hasn't lost many elections since coming to power, the defeat of his Constitutional referendum is very telling. The 'No' vote won: 51% to 49%. Many speculate that Chavez lost because a large bloc of his supporters abstained from voting. This article gives the reasons why.
As the article points out, Chavez is already figuring a way around the referendum defeat. Time will tell the effect on Venezuela if he is able to get his proposals through via a different avenue.