If you have an opinion one way or the other, call or e-mail your Senator and let them know.
If you oppose Bernanke's re-confirmation, but you're not sure what to say, you might start with:
Dear Senator [so-and-so],The vote for cloture (to end a filibuster blocking a vote on his re-confirmation) looks to be close right now, so your input may make a difference if your Senators have not decided yet.
I am a resident of [City, State] and ask that you please oppose the re-confirmation of Ben Bernanke for Federal Reserve Chairman. Bernanke has proven he cannot fulfill the Federal Reserve's dual mandate of price stability and full employment and thus has shown he is not qualified to serve a second term as Chairman.