President Obama is endorsing the congressman who drew headlines recently for suggesting the island of Guam might "tip over and capsize."
Johnson has been battling Hepatitis C, which has made his speech slow and caused him to lose a lot of weight. But he has said he will press forward with serving in Congress.
At the same time, he has drawn primary challenges from former DeKalb County CEO Vernon Jones and DeKalb County Commissioner Connie Stokes.
The endorsement of a black lawmaker in a majority-black district is a rare one for Obama. In 2008, he drew some heat from African-Americans for backing white Rep. John Barrow (D-Ga.) over a black state senator in Barrow's primary. That led black lawmakers facing their own primaries to wonder why he wasn't helping them.
The Johnson endorsement could set a precedent for other black lawmakers seeking the president's help this year.