A American supported coup in Latin America have as much support from the general public as Russian ones in the Eastern Europe. So congratulation if Obama followed your suggestion, we could look forward to a decade with Maduro.
If the coup plotters restore democracy after the coup (probably the best possible result), I highly doubt the Venezuelan people will cut off their nose to spite their face by voting for Maduro.
There is nobody within the Venezuelan system who would be capable of pulling off a coup, as such, against Maduro; thus, any attempt at doing so would be crushed, and probably provide Maduro a decade's worth of propaganda fodder.