Most of the opposition is likely to come from Republicans, like Alabama Senator Jeff Sessions, who object to the fact that Lew does not embrace the European-style austerity agenda that they seek.
But just because economic reactionaries like Sessions are opposed to Lew does not mean that he is the right person to take charge of the Treasury Department. There is great danger in approaching fundamental questions about the nation's direction with a simplistic "the-enemy-of-my-enemy-is-my-friend" approach. Economic and fiscal policy choices need to be more nuanced, and principled than that.
So it is healthy, very healthy, that Lew will face opposition from those on the left -- led by Sanders -- who recognize that a big part of what ails the American economy can be traced to the Wall Street-to-Washington revolving door through which Tim Geithner and Jack Lew have passed.