WASHINGTON (CNN) -- The emotional debate over the war will once again dominate presidential politics when all three candidates have opportunities to question the top U.S. general in Iraq during congressional hearings Tuesday.
Sen. John McCain, the presumptive GOP presidential nominee, and Sens. Hillary Clinton and Barack Obama, the two rivals for the Democratic nomination, will share the spotlight when Army Gen. David Petraeus and Ambassador Ryan Crocker, the top U.S. diplomat in Iraq, testify.
McCain and Clinton will question Petraeus and Crocker -- and possibly advocate their positions on whether U.S. troops should be withdrawn -- when they appear before the Senate Armed Services Committee on Tuesday morning. McCain is the committee's top Republican.
Obama, of Illinois, will have his chance to question Petraeus and Crocker when they appear before the Senate Foreign Relations Committee on Tuesday afternoon. Watch how presidential candidates will be highly visible at hearings »
Petraeus is expected to recommend a pause in the withdrawal of troops from Iraq after July, when the troop levels will be lowered to roughly the number deployed before President Bush agreed to a "surge" of troops into the country in early 2007.
Despite the war being hugely unpopular, McCain has been a strong advocate of continuing the U.S. deployment, arguing that a precipitous departure would permit Iraq to fall into chaos. Watch McCain call a hasty withdrawal 'reckless' »
Speaking at the headquarters of the Veterans of Foreign Wars in Kansas City, Missouri, on Monday, McCain touted the success of the surge, saying it had led to reduced violence and increased security after "four years of a badly conceived military strategy."
"There is no doubt about the basic reality in Iraq: We are no longer staring into the abyss of defeat, and we can now look ahead to the genuine prospect of success," he said.
"If we withdraw hastily and irresponsibly, we will guarantee the trouble will come immediately. Our allies, Arab countries, the U.N. and the Iraqis themselves will not step up to their responsibilities if we recklessly retreat," he said. "I can hardly imagine a more imprudent and dangerous course."
The Arizona senator's position on the war is in stark contrast with the stands of Clinton and Obama. Both have said they would begin withdrawing combat brigades from Iraq almost immediately after taking office.
The two also say that a drawdown in Iraq would free resources for fighting in Afghanistan and help restore the U.S. image in the world.
"Restoring moral authority in the world starts with ending war in Iraq," Clinton told supporters in Grand Forks, North Dakota, last week.
Obama expressed similar sentiments when he spoke to Democrats in Butte, Montana, on Saturday.
"I believe that the United States of America can remain the last, best hope of Earth," he said. "We can end this war in Iraq, win this war in Afghanistan, rebuild our alliances and restore our moral standing by leading the world against the common threats of the 21st century -- terrorism and nuclear weapons, poverty and climate change, genocide and disease."
Petraeus and Crocker's testimony comes a week after a new National Intelligence Estimate on Iraq was delivered to lawmakers. The classified document says Bush's troop surge had reduced violence in the country, congressional sources with knowledge of the report told CNN.
Senior Democratic senators Friday challenged the report's surge assessment, saying the increase in troop levels has failed to achieve its strategic goals. The surge has not resulted in the political reconciliation it was meant to achieve, the Democrats said.
Democratic congressional sources also said the NIE does not take into account the most recent events in southern Iraq, but they didn't expect it to.
Bush administration officials have declined to characterize the findings of the NIE, largely because they do not want to get ahead of the public testimony from Petraeus and Crocker. E-mail to a friend