From the above article:
As Sunday's referendum vote approaches, all indications are that it enjoys the support of a clear, and increasing, majority of the Venezuelan electorate. This fact is borne out in recent polling data released in Venezuela by polling firm GIS XXI. According to the polling firm, 52.9% of voters currently support the effort to eliminate presidential term limits, with only 40% opposing. Moreover, when faced with the statement, "If the people support him, President Chávez has the right to run in the elections as many times as he likes," nearly 70% expressed agreement, and almost 75% characterize the President's leadership as either "very good" or "good." The more independent Venezuelan Data Analysis Institute (IVAD) has, surprisingly, given a more significant margin of victory to the "yes" vote, which it estimates at 54.6% versus 45.5% against (the margin separating the two having increased a full 3 points in recent weeks).
Even Datanálisis, a notoriously anti-Chavista polling firm whose director once insisted to the Los Angeles Times that Chávez needs to be assassinated, currently gives the referendum a margin of more than 3 points. While such a margin may seem unsurprising to anyone familiar with the reigning political atmosphere in Venezuela, it comes as somewhat of a surprise from Datanálisis, which just in December had the referendum losing by nearly 15 percentage points. And another opposition pollster, Hinterlaces, shows the election to be a dead heat, but does so only on the basis of misleading, urban-only polling, knowing full well that Chávez regularly outpolls the opposition by more than 20% in rural areas. http://www.venezuelanalysis.com/analysis/4209--------
The writer lays out very clearly why "Yes" has improved from a dead heat to as much as a 5% lead: the idiocy of the opposition (for instance, rightwing students getting caught with a truckload of molotov cocktails), combined with new energy and mobilization by Chavez's support base. He has enjoyed high approval ratings all along--so it's just a matter of getting out the vote. He wants to run for a third term, and it looks like he will be able to.
This writer (George Cicariello-Maher) misses one likely reason why lifting the term limit failed in Dec 07 referendum. It was combined with equal rights for women and gays--among a total of 69 amendments on a wide variety of issues. Venezuela is a Catholic country with a particularly rightwing (and political) clergy. The opposition ran ads saying that the 69 amendments would result in the government taking children from their mothers. The hot button equal rights issue and the complexity of the ballot (which the writer mentions as the chief cause of failure) caused 10% of normally pro-Chavez voters to abstain or vote "No." It was a very close vote (50.7% vs. 49.3%). That religious complication is not present in the current referendum, which is a very simple issue: pro or con, term limits for president and other offices (including governors and mayors).