Empty supermarket shelves are not exactly a good look for the president and his economic team.

So, circumstances look dramatically more challenging for the Democrats now than they did last spring.

My longtime friend Charlie Cook was, of course, exactly right when he wrote recently that Senate races are more idiosyncratic than House races and that “House and Senate results are hardly synchronized.”

Historically, the quality of Senate candidates are better, many Senate challengers raise enough cash to run competitive campaigns, and outcomes depend on which combinations of states are having Senate contests in a particular year.

Still, Senate “wave elections” are not unheard of.