Long viewed as an ally by Wall Street, likely 2016 presidential contender Hillary Rodham Clinton has increasingly been taking banks and big business to task while on the campaign trail for Democrats across the United States.

Many Democratic strategists see the sharper rhetoric as an effort to win over liberal critics, such as supporters of Massachusetts Sen. Elizabeth Warren. It comes days before Tuesday's midterm elections and as Clinton ramps up her political activity ahead of a probable White House bid.

"Al has pushed for more and better oversight of the big banks and risky financial activity," Clinton said in support of Sen. Al Franken in Minnesota in late October, in the starkest example yet of her populist turn. "There's a lot of unfinished business to make sure we don't end up once again with big banks taking big risks and leaving taxpayers holding the bag."