After a lot of hand-wringing over inter-party squabbles and "endangered" incumbents, Congressional lifers Orrin Hatch and Charles Rangel easily passed their primary challenges on Tuesday, signaling almost certain re-election in the fall. Hatch, who has been a Senator for Utah since 1976, crushed his Tea Party-opponent with nearly double the number of votes. Meanwhile, Rangel (who represents New York's 15th District centered in Harlem) won 45 percent of the vote in a crowded Democratic field.

The fact that these two races were considered to be among the toughest of either politician's career shows just how hard it is to unseat a incumbent once they set down roots in Washington. In 2010, Rangel became the first member of the House of Representatives to be censured on the floor of the chamber in more than three decades and lost his chairmanship of the powerful Ways and Means Committee due to ethics violations, but has already been re-elected once and will likely cruise to victory in November. Hatch's win was never really in doubt, but simply being challenged by a fellow Republican was enough to make some supporters nervous and make national headlines.

There was one primary upset, however, as four-term Oklahoma representative John Sullivan was knocked off by Navy Reserve pilot Jim Bridenstine. Sullivan is this year's exception that proves the rule, as he's the first Oklahoma incumbent to lose his seat in 18 years.

The Utah primary was also the last presidential contest of the GOP primary season, giving Mitt Romney his final collection of delegates before the Republican National Convention.