Of seven potential new additions to U.S. diplomatic missions that the Senate Committee on Foreign Relations will consider at a hearing Tuesday afternoon, three are among President Barack Obama's most successful fundraisers from his 2012 campaign.

The president's most recent flight of would-be ambassadors follows a familiar pattern: a mix of career members of the Foreign Service and mega-campaign bundlers. 

Presidents have long reserved around 30 percent of available ambassadorships for political allies -- using plum diplomatic posts in U.S.-friendly nations to function as rewards for campaign loyalty. The widely-accepted practice has persisted for more than ...