Control of the Senate in 2008 could potentially turn on the question of whether Senator Tim Johnson (D-SD) will run for re-election. Johnson, after all, underwent emergency brain surgery several months back, and has been occupied with physical therapy instead of the action on the Senate floor.

Now Robert Novak reports in his latest column that Johnson will definitely run:

Contrary to rumors, well-placed Democrats are positive that former Senate Majority Leader Tom Daschle (D-S.D.) will not run for the Senate next year in place of incapacitated Sen. Tim Johnson (D-S.D.). National party operatives who have talked to Johnson on the telephone say he is improving rapidly, raising lots of money and definitely will run. Democrats fear Gov. Mike Rounds (R-S.D.) would run against Daschle, but not Johnson.