An explosion at Venezuela’s largest refinery that killed at least 48 people and injured dozens on Aug. 25 is threatening to cast a shadow over President Hugo Chavez’s re-election bid.

The blast and ongoing fire at Amuay, 240 miles west of the capital, Caracas, adds to a number of events in recent weeks that have fueled concern over mismanagement, including a collapsed bridge connecting Caracas with the east of the country, deadly prison riots and protests by state workers over collective contracts.

Chavez will need to divert blame from a poor refinery maintenance record to avoid political fallout ahead of the Oct. 7 vote, said Luis Vicente Leon, president of Caracas-based polling firm Datanalisis. The self-declared socialist, who is seeking to extend almost 14 years in power with another six-year term, trailed his opponent, Henrique Capriles Radonski, for the first time in a Consultores 21 poll earlier this month.