Two candidates have overtaken Pedro de la Rosa as favourites to become Bruno Senna's 2010 teammate at Campos.
The Spanish team's chief Adrian Campos has this week revealed that his desired collaboration with de la Rosa, McLaren's main test driver, is likely to fall over due to a lack of corporate backing.
"I would like to have Pedro de la Rosa, but he is Spanish and there are problems with the sponsorships of Spaniards," he said.
"There are other options from Russia and Venezuela, but everything depends on the sponsors," Campos added.
Team president Jose Ramon Carabante clarified that Pastor Maldonado is the front-running Venezuelan, while the Russian referred to by Campos is Vitaly Petrov.
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