The Justice Department's Public Integrity Section mishandled a Ted Stevens case. Now, it's under the microscope as it presses forward with charges against John Edwards.
Sen. Tom Coburn and former Sen. Rick Santorum appear to have been involved in the scandal that brought down former Sen. John Ensign. A Senate Ethics Committee investigation could lead to criminal charges for Ensign.
Facing scandal, Sen. John Ensign (R) of Nevada is resigning. That allows Republican Gov. Brian Sandoval to name a replacement, which in turn could open up a US House seat.
Sen. Claire McCaskill already was going to face a tough 2012 reelection in Missouri. But news about unpaid taxes on – and questionable use of – her plane are weighing on the Democrat's chances.
Retirement of Sen. Byron Dorgan means it will be harder for Democrats to keep their filibuster-proof Senate majority after 2010. But the exit of Sen. Christopher Dodd improves Democrats' chances of holding onto his seat.
Calls grow for him to resign as a perjury probe proceeds.
John McCain's military experience and Senate record show a presidential candidate who values integrity and getting things done.