Republican U.S, Sen. Johnny Isakson announced today that he will retire at the end of the year for health reasons. Isakson's decision creates a Senate race doubleheader in November of next year.

Once Isakson's retirement is official, likely when Congress leaves for the holidays in December, Republican Gov. Brian Kemp will name a replacement who will hold the seat until, and presumably compete in, the special election next year. Republicans have a deep bench of potential appointees, including state Attorney General Chris Carr, Lt. Gov. Geoff Duncan, and many of the nine Republican members of the state's congressional delegation.  The appointee should be sworn in by the start of the next session in January of next year.

Democrats have great hopes that they can make the other Senate seat, where GOP U.S. Sen. David Perdue will seek a second term, competitive. At this point, the party doesn't have what it considers a strong frontrunner among the three announced candidates — 2018 LG nominee Sarah Riggs Amico, Clarkston Mayor Ted Terry, and former Columbus Mayor Teresa Tomlinson. It's possible that one of them could move over to the Isakson seat, but for now Democrats need yet another candidate.  The first name that comes to mind is 2018 gubernatorial nominee Stacey Abrams, but Abrams has already passed on the Perdue seat. Her spokesman put out a statement this morning stating that Abrams would stay focused on her national voter protection effort. In truth, Abrams has always been more interested in being Governor than serving in the U.S. Senate. The names of other potential candidates will begin to emerge over the next few days.

It's hard to rate a race without knowing the identity of the Republican appointee, or names of interested Democrats.  As such, we will park the contest in the Likely Republican column until we know more.

Image: AP Photo/Alex Brandon

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