No, there is good reason to believe the election was fair. The mainstream U.S. reporting on this is extremely biased; the U.S. has a long history of deeply anti-democractic attitudes towards Latin America (since at least the Monroe Doctrine). Excellent and detailed reporting here:[1]

"...key opposition candidates in the governor's races in Venezuela are gradually accepting the results as legitimate, except for one controversial close race that is being challenged in the State of Bolivar where opposition has some serious allegations due to the discrepancy in the results that the CNE announced, that's the election commission in Venezuela, the results that they announce and the printout of the report that was given to each party by the voting machines."

"ALEXANDER MAIN: First of all, it's really nothing new... Already in 2002, much of the corporate media internationally was suggesting that the presidency of Chávez had become something of a dictatorship and completely ignoring some of the anti-democratic activities of the opposition parties in Venezuela, and namely a coup d'etat was supported by most of Venezuela's opposition parties in April of 2002. This was initially represented as some sort of a popular uprising against the dictatorship, and it was really, I think, thanks to the reaction of other governments in the region that clearly saw that there was a coup d'etat that the narrative began to change around that.

"Soon afterwards, we got back into this tradition of suggesting that there was creeping authoritarianism going on in Venezuela. Very little was said about the fact that nearly every year, sometimes twice a year in Venezuela, you had elections being held at different institutional levels. These elections would typically have very big turnouts, they'd be very transparent, very free and fair... In fact, it can be argued that the electoral system in Venezuela has gotten more and more refined in terms of the degree of transparency, to the extent that in fact, it [speaks] in part to that transparency and the internal checks and balances that today you do have this controversy in the state of Bolivar... They can do this, in fact, because they have records from electronic voting machines, which everyone believes... the fact is that you have a system that's in place that can very easily allow for verification... It really is sort of a direct contradiction of this constant claim that the country is slipping into dictatorship. You don't have that when you have constant elections in which people, the majority of voters participate and where you can have confidence in the results."

[1] http://therealnews.com/t2/index.php?option=com_content&task=...