Venezuelan Vice President Nicolas Maduro would win a presidential vote should his boss Hugo Chavez's cancer force him out, according to the first survey this year on such a scenario in the South American OPEC nation, Reuters reported.

Local pollster Hinterlaces gave Maduro 50 percent of potential votes, compared to 36 percent for opposition leader Henrique Capriles.

Chavez made a surprise return to Venezuela on Monday, more than two months after cancer surgery in Cuba, to continue treatment at home for the disease that is jeopardizing his 14-year socialist rule. He has named Maduro, 50, a former bus driver and union activist, as his preferred successor.

Capriles, 40, a center-left state governor who lost to Chavez in a presidential vote last year, likely would run again.

Chavez still has not spoken in public since his December 11 operation in Cuba. Venezuelans were debating on Tuesday the various possible scenarios after his homecoming - from full recovery to resignation or even death from the cancer.

There was widespread expectation Chavez would soon be formally sworn in for his new six-year term at the Caracas military hospital where officials said he was staying. The January 10 ceremony was postponed while he was in Cuba.