Democrats won Congress in a blue wave. Now comes the hard part.

Americans' frustration with Congress' productivity was palpable before the election. Only 14% of US registered voters approved of lawmakers' performance, an October Gallup poll suggested.

But with a Republican in the White House and Democrats running Congress, Americans may face even more deadlock.

"If you thought legislating was hard in the last Congress with unified Republican control, that will get much more complicated," said Casey Burgat, professor of legislative affairs at George Washington University.

Because they will control both chambers with a comfortable majority, Democrats will be able to pass legislation through Congress with relative ease.

Getting it enacted into law will be harder.