Today’s Morning Browser was completely taken over with shocking news out of Tennessee’s 8th District that Rep. John Tanner (D-TN) will not seek re-election to U.S. Congress.

The shock continued with news that State Sen. Roy Herron (D-Dresden) dropped out of TN’s 2010 Democratic gubernatorial primary to run for the open seat.

Here’s an excerpt from the Memphis Flyer:

In a shocker, 8th District U.S. Representative John Tanner of Union City, a conservative “Blue Dog” Democrat and a veteran of 22 years’ service, announced late Tuesday that he will retire next year instead of running for reelection. Tanner had been facing a serious challenge from Republican Stephen Fincher, who had raised almost $300,000 over the last few weeks and was gaining momentum.

Tanner’s withdrawal from a reelection race leaves Tennessee’s once-dominant Democrats in an ever more precarious situation, with no immediate successor to carry the party standard in a conservative district that is thought now to be trending Republican.