The Sun-Times had an article on Sunday about a change in Sen. Obama's game plan for this year. He's going to go on the attack against some of the GOP's recent ethics challenges. Of course the spotlight has been on the Senator recently with regards to his using private jets with campaign donations instead of using a cheaper first-class airfare.
The Sun-Times article refers to this as Obama "breaking from his bipartisan honeymoon and preaching the Democrats' party line on ethics." He is taking a leading role in a Democratic ethics campaign in time for the 2006 campaign. This may be key in the possibility of Democrats taking back the US Congress this year.
We'll have to see where this pans out.