WASHINGTON -

First it was Chris Christie, humbled by members of his staff who shut down a bridge from New Jersey into Manhattan in an apparent act of political retribution.

Now it's Scott Walker, who prosecutors in Wisconsin believe acted criminally by coordinating the fundraising and spending of outside conservative groups.

They're two of the nation's highest-profile Republican governors, both with hopes for the White House in 2016. And in a midterm election year, when would-be presidential candidates like to showcase their accomplishments, they are instead dealing with controversies at home.

For Christie, the story has moved on to his recovery. For Walker, the troubles may be just beginning. Documents released Thursday put him at the center of an investigation into campaigns in 2011 and 2012.

No one has been charged and both men say they did nothing wrong.