On the day Congress is due vote on Barack Obama’s recovery plan, the US President has been undermined by the withdrawal of another nominee for his cabinet.Senator John Gregg said he could not take up the post of Commerce Secretary because of fundamental policy differences. He would have been third Republican on Obama’s cabinet. It is a set back for Obama’s efforts to create an administration bridging the political divide. Republicans have been voicing increasing opposition to the economy plan. The House of Representatives is expected to vote on the stimulus package later today. Analysts expect it to be approved eventually, but not with the Republican support Obama had been hoping for.