KWAME HOLMAN: In Columbus, Ohio, Obama wondered what prompted Clinton's outrage.
SEN. BARACK OBAMA (D), Illinois: In terms of the two mailers that she specifically referred to here, these are mailers that, by the way, started going out several days ago, if not weeks ago.
So I'm puzzled by the sudden change in tone, unless these were just brought to her attention. It makes me think that there's something tactical about her getting so exercised this morning.
And unlike some of the attacks that have been leveled about me that have been debunked by news organizations, these are accurate.
KWAME HOLMAN: At a rally in Cincinnati this afternoon, Obama reminded supporters of his opposition to NAFTA without drawing comparisons to Mrs. Clinton.
SEN. BARACK OBAMA: We're going to have a trade system that is free and fair. See, I believe in trade. I believe all countries can prosper from globalization. But not if our trade agreements don't have strong labor standards, strong environmental standards, so that U.S. workers aren't being undermined.
NAFTA didn't have those things, and that's why I opposed NAFTA, safety standards so our children aren't chewing on toys with lead paint and patients aren't taking medicines made overseas that actually make them worse.
We're going to change our trade agreements so that they reflect the interests not just of Wall Street, but also of Main Street.
KWAME HOLMAN: However, the sparring between the campaigns continued without the candidates today over a photo that turned up on the online Drudge Report showing Obama in 2006 dressed in traditional Somali garb.
The Obama campaign accused Clinton's campaign staff of planting the photo and of engaging "in the most shameful, offensive fear-mongering we've seen from either party in this election."
The Clinton campaign insisted it did not know the source of the photo, but argued the Obama response was an "attempt to create the very divisions they claim to decry."
Meanwhile, following a rally outside of Cleveland this morning, Republican John McCain still was answering questions about last week's New York Times story about his relationship with a female communications lobbyist.
Follow-up stories this weekend raised new questions about a letter McCain wrote to the Federal Communications Commission on behalf of one of the lobbyist's clients.
SEN. JOHN MCCAIN (R), Arizona: The letter I wrote said, "Do not make any decision either way for either person or either party." I said, "I am not asking you to say anything favorably or unfavorably."
That's the key to it. The key to it is that I said, "Just make a judgment."
My job as chairman of the Commerce Committee is to oversight the bureaucracies of Washington. And if there's some inordinate delays of some 800 days, then it's entirely appropriate to ask a bureaucracy to function. That's the oversight responsibilities.
I'm proud to have led on campaign finance reform, on ethics reform, never taking a single earmark project in the 24 years I've been in Congress. I am proud of my record of reform, of reform, that I have sought and fought for and change and achieved to a large degree.
KWAME HOLMAN: Mike Huckabee, who has refused to be drawn into the McCain lobbyist story, campaigned today in Rhode Island.