Unlike Ohio Sen. Rob Portman's retirement decision two weeks ago, the announcement Monday by Alabama GOP Sen. Richard Shelby that he won't run for re-election next year has been widely expected. The senior senator would have been 88-years-old by the midterms and 94 by the end of a potential seventh term. In a state that's solidly Republican and the only one where the GOP flipped a seat from blue to red last November, the contest remains in the Solid Republican column. Alabama is the fourth open Senate seat so far ahead of 2022.

Shelby himself is evidence of how much Alabama has changed politically over the past few decades. After eight years in the House, he was first elected to the Senate in 1986 as a Democrat, helping his then-party flip control of the Senate in Reagan's second midterm election. But in 1994, the morning after the Republican Revolution swept the GOP back into control, Shelby switched parties. He's been easily re-elected since. His seniority and stature helped him direct millions of dollars for federal projects back to his

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