The presidential candidates are sure to use the appearance of Gen. David Petraeus and Amb. Ryan Crocker on Capitol Hill Tuesday as an opportunity to play out this season's election drama over who has the best approach to dealing with Iraq.

Democratic Sens. Hillary Clinton and Barack Obama are vying over who opposed the war earliest and most vocally. Sen. John McCain, the presumptive Republican nominee, is arguing that they are both wrong. All three will be part of the theatrics on Tuesday.

Clinton, speaking with FOX News Tuesday morning, made clear that she does not believe the surge has succeeded in its goal to bring Iraq political progress.

"The fact is the stated purpose of the surge last year was to give the Iraqi government a push by trying to create some space and time for it to make decisions that it had to make. And that hasn't happened," Clinton said, pointing to recent comments by Petraeus that political reconciliation isn't what one would have expected.

Clinton said recent fighting in southern Iraq as well as Sadr City in Baghdad is a result of Iraqis' inability "to move forward."

"The Iraqis I think believe they've been given a blank check by George Bush," Clinton said.

"If I'm president, I will begin to withdraw troops and I will do it carefully and responsibly, but I will make it clear to the IRaqis that there is no military solution. It's up to them,' she said.

McCain is sure to use his role as a senior member of the Senate Armed Services Committee to gain the spotlight. The Armed Services panel is the first to hear from the two leaders. Clinton is a relatively junior member of that committee so she will be close to the end of the morning's hearings.

Obama is a junior member of the Senate Foreign Relations Committee and will be about 13th in line to question Petraeus and Crocker, an opportunity that probably won't present itself until after the evening news on Tuesday.

The candidate to make the most gains is likely the one who can best parse the testimony being offered by the top U.S. military commander and diplomat in Iraq. The two are addressing the Senate Armed Services and Foreign Relations committees on Tuesday and follow up Wednesday before the respective House panels.

Both Sens. Carl Levin and Joe Biden, chairmen of the Senate committees, say they will not allow the hearings to be used as a commander in chief dress rehearsal. The candidates will not be given any special attention and they will be treated as any other senator in the hearings.

McCain, who's been banking his campaign on his national security credentials, tried to get a leg up on Monday when he gave a speech to Veterans of Foreign Wars in which he criticized his Democratic opponents for not being realistic about Iraq.

McCain said if they are given a candid assessment and are dealt with honestly, Americans will be patient about the time necessary to obtain U.S. objectives in Iraq. He added that Hillary Clinton and Barack Obama shouldn't take the opportunity to try to hijack the hearings with their own agendas.

"Doing the right thing in the heat of a political campaign is not always the easiest thing. But when 4,000 Americans have given their lives so that America does not suffer the worst consequences of our failure in Iraq, it is a necessary thing. In such a grave matter, we must put the nation's interests before our own ambitions," he said.

He added that the reality in Iraq is "we are no longer staring into the abyss of defeat, and we can now look ahead to the genuine prospect of success."

The Democrats both responded that McCain is a broken record, and continued to try to tie him to the policies of the Bush administration.

"It's a failure of leadership to support an open-ended occupation of Iraq that has failed to press Iraq's leaders to reconcile, badly overstretched our military, put a strain on our military families, set back our ability to lead the world and made the American people less safe," Obama said. "John McCain was wrong about the war from the beginning, he's wrong to call for more resources in Iraq while the American people are struggling and he's wrong to support a 100 year occupation of a country that needs to take responsibility for its own future."

"Senator McCain's Groundhog Day approach to Iraq means four more years of the Bush-Cheney-McCain policy of continuing to police a civil war while the threats to our national security, our economy and our standing in the world mount," Clinton said in her own statement. "We simply cannot give the Iraqi government an endless blank check. It is time to end this war as quickly, as responsibly and as safely as possible."

McCain has often argued that he'd rather lose the presidency than lose the war in Iraq, but both goals have been helped lately by improvements on the ground. Yet an uptick in skirmishes among Shiite militia members and Iraqi security forces will likely give Petraeus a reason to reject calls for more troops to be withdrawn beyond the number expected to be out by July, a point that Democrats will try to exploit.

Petraeus and Crocker will likely tell the candidates what they were already expecting to hear. The length of troop deployments can be reduced back to 12 months from an extended 15. The number of brigades in Iraq in July will be 15 -- equal to the 140,000 or so who were there before last year's surge.The two are also expected to lobby for more cash to fund operations on the ground. Congress has not yet acted on President Bush's request last year to add an additional $100 billion or so to run Iraq operations through September.

While the argument may make for fodder on the campaign trail, Democrats in the House and Senate are unlikely to put a stop to funding the troops.

However, the Clinton and Obama campaigns have been closely involved in crafting Democratic strategy over financing the war, and could make a big deal about claiming the fighting in Basra is a civil war that requires U.S. troops to step back. That kind of appeal could work on moderate Republicans like Sens. John Warner and Dick Lugar.

Democrats are also looking to exploit the funding divide, noting that the U.S. is spending at a ratio of about 11 to 1 on reconstruction in Iraq. The question to be answered is whether the Iraqis have appropriated the money but don't have the bureaucracy yet to distribute it.

FOX News' Jennifer Griffin and Trish Turner contributed to this report.