According to CNN, off the record sources have told them that Karl Rove has offered the Secretary of Agriculture to Democratic Senator Ben Nelson of Nebraska. Nelson won't confirm discussion with Rove.
If Nelson would accept, Republican Gov. Mike Johanns would get to choose Nelson's replacement, which could increase the GOP's advantage in the Senate to 56 seats. Which would be a disaster because this seat is as golden to the Democrats as Chafee's is to the GOP. Even more so because the Dems are in the minority and getting an other GOP Senator brings them afwfully close to the 60 vote cutoff border...
Nelson faces a tough reelection fight in 2006 against possibly Gov. Mike Johanns who is term limited.
Currently, the only Democrat in Bush's Cabinet is Transportation Secretary Norman Mineta.
http://www.cnn.com/2004/ALLPOLITICS/11/17/agriculture.secretary/index.html