Now let's look little more deeply at this narrative of scandal. NPR's Scott Horsley has more.
SCOTT HORSLEY, BYLINE: When President Obama gets frustrated with the gridlock in Washington, he sometimes looks back wistfully to the decades after World War II. Back then, he suggests Republicans and Democrats managed to work together, despite their differences, building highways, protecting consumers, and educating generations of workers.
The phrase "second term curse" is so familiar that it's become a cliche of American politics. Whether it's President Richard Nixon's resignation or President Bill Clinton's impeachment, presidents tend to have a tough time during the back half of an eight-year presidency.
Gov. Scott Walker embarks on a speaking frenzy this week. He’s set to keynote huge Republican gatherings in Connecticut and New York City, then head to Iowa, to be the star of a GOP gathering. Iowa is home to the nation's first presidential caucuses.