Apr. 9, Feature - The three Presidential candidates returned to their day job, for one day as US commander in Iraq, General David Petreaus and Iraq Ambassador Ryan Crocker defended current Iraq policy to, possibly, their future boss, at Senate hearings on Iraq. But still embroiled in the Presidential campaign, the candidates attempted to differentiate themselves on the war.

Presumptive Republican nominee, John McCain, is top Republican on the Senate Armed Services Committee.

He again warned against a withdrawal of US troops, and he claimed 'success' in Iraq.

"Today it is possible to talk with real hope and optimism about the future of Iraq and the outcome of our efforts there. While the job of bringing security is not finished as the recent fighting in Basra and elsewhere demonstrated. We're no longer staring into the abyss of defeat. We can now look ahead to the genuine prospect of success."

Protestors interrupted McCain's testimony...

(Protestor at hearing:) "..Bring Them Home, Bring Them Home.."

McCain focused much of his testimony on Al Qaeda in Iraq and on Iran's influence in Iraq.

"I hoped we could talk about the Iranian threat particularly their stepped up support of various elements that are Shiite extremists in Iraq, particularly the role they played in Basra and the Southern part of the country."

Democratic candidate Barack Obama also focused on Al Qaeda in Iraq and Iran. He seemed to be laying the groundwork of directives as Commander in Chief. He called for discussions with Iran over Iraq and he wanted a sense of the US's objectives there.

"There's a bi partisan consensus we have finite resources. Our military is overstretched and the pentagon has acknowledged it. When you have finite resources, you have to define your goals tightly and modestly, I'll even pose this as a question and you don't have to answer, maybe it's a rhetorical question, if we were able to have the status quo in Iraq right now, would that be some definition of success? If we had the current status quo, and our troops had been drawn down to 30,000 would that meet our criteria"

"Senator I can't imagine the current status quo being sustainable with a precipitous drawdown"

".. the problem I have is if the definition of success is so high.. no traces of Al Qaeda, a highly effective Iraqi government, a democratic multi ethnic, multi-sectarian functioning democracy, no Iranian influence.. then that portends the possibility of us staying there for 30 or 40 years. If on the other hand our criteria is messy, sloppy, status quo but there's not huge outbreaks of violence... that seems to me an achievable goal with in a measurable time frame.. "

Democratic candidate Senator Hillary Clinton was direct in her call to 'start' withdrawing troops. But she focused on, as she has during much of her run for President, on an agreement between President Bush and Iraqi Prime Minister Nouri Al-Maliki that would ensure long term US involvement.

"Will the Iraqi government submit an agreement to the Iraqi Parliament for ratification?

"It is unclear to me whether that will be for a formal vote or whether they will repeat the process they used in November for the Declaration of Principles which it was simply read to the members of Parliament."

"Does the administration plan to submit this agreement to our congress?"

"We do not anticipate that the agreements will have with in them any elements require the advise and consent procedure. We intend to negotiate this as an executive agreement."

".. it seems odd to Americans who are being asked to commit for an indefinite amount of time… if the Iraqi parliament may have a chance to consider this agreement, that the US Congress may not.. And as you may not I currently have legislation requiring the congress to have an opportunity to consider such an agreement before it is signed. And I encourage you to submit such an agreement to the Congress for full consideration.

All three candidate will take that message back on the campaign trail.