It might be the case that fraud was unnecessary for the Chavez win. But if fraud was necessary, then fraud was committed. There is virtually no chance Chavez was going to be allowed to lose.
The lede says it all [emphasis mine]:
With 90 percent of the votes in, President Hugo Chavez was declared the winner in the Venezuela presidential election. Chavez received 54 percent of the vote to serve an unprecedented third term after he changed the country’s constitution, NBC News reported.
I’ll close with my favorite quotation from Dostoevsky’s Grand Inquisitor, from The Brothers Karamazov:
In the end they will lay their freedom at our feet, and say to us, “Make us your slaves, but feed us.”