Where do 2016 contenders stand on the military fight against ISIS?

This week, the Obama administration is expected to send Congress a request for an authorization for the use of military force (AUMF) against the Islamic State of Iraq and Syria (ISIS). The document, reports CBS Congressional Correspondent Nancy Cordes, attempts to define a middle ground between Democrats leery of another protracted Middle Eastern conflict involving ground troops, and Republicans, who largely believe the U.S. needs maximum flexibility to pursue ISIS.

The AUMF, as drafted by the White House, will open the door for the use of ground troops in some scenarios, but it will prohibit "enduring offensive ground forces." Defining "enduring" will be a central feature of the debate to come.

A version of the legislation that passed the Senate Foreign Relations committee in December -- while the Senate was still under Democratic control -- would only have allowed the use of ground troops for specific operations, like rescuing a U.S. service member if their plane was downed in Syria. That AUMF drew only Democratic support in the committee.

The politicians considering a run for the White House in 2016 largely support a new AUMF, but there are variations in what they'd like to see in it. And whoever takes over after President Obama will almost certainly be bound by whatever legislation Congress passes in the coming months.

"This is a long-term effort that will go well beyond President Obama's administration," Tom Donilon, Mr. Obama's former National Security Adviser, said on "Face the Nation" Sunday.

Here's what some of the potential contenders have to say:

Sen. Lindsey Graham, R-South Carolina: Graham, told CBS News' John Nolen, "If we are not willing to destroy ISIL through a rational strategy, they will survive." Graham, who serves on the Senate Armed Services Committee and will cast a vote on the AUMF, insists that U.S. ground troops must be part of the equation: "If you' re not willing to have an American ground component, there's no local force can do this completely by themselves. So, to me it's all talk. You are not going to destroy ISIL from the air, there has to be ground component. Show me the ground component, where it comes from and how it can destroy ISIL without some American ground force support. You can't do it, in my view."

Sen. Rand Paul, R-Kentucky: Paul hasn't seen the president's legislation, but in December, he introduced his own measure that would end the 2002 Iraq AUMF and set an expiration date on the Afghanistan AUMF. Paul's measure sounds similar to what is known about the administration's legislation. His version -- which would expire one year after enactment -- would declare war on ISIS and allow limited use of ground forces in special cases, like the rescue of military forces or civilians from ISIS or for special operations against high-value targets.

Sen. Ted Cruz, R-Texas: Cruz hasn't yet weighed in on the reports about what the president will propose, but he has been clear in the past that he won't support any legislation that requires a political reconciliation in Iraq. In September, when Mr. Obama prepared to deliver a speech about the strategy to fight ISIS, Cruz wrote in an op-ed that he hoped Mr. Obama would propose "a clear plan, consistent with the Constitution, to keep Americans safe, and that it is not laden with impractical contingencies, such as resolving the Syrian civil war, reaching political reconciliation in Iraq or achieving 'consensus' in the international community."

Sen. Marco Rubio, R-Florida: Rubio appears to favor a broad authorization for the use of force against ISIS, though he thinks the ground troops should be contributed by Arab countries in the region. In an interview on Fox News Tuesday night, he also opposed geographic limits on an AUMF. "If you put a geographic limit on the authorization of the use of force you've basically told ISIL where they can go to hide," he said. That's consistent with his vote against an amendment offered by Paul during the Senate Foreign Relation Committee's debate on AUMF legislation last December that would have limited U.S. operations to Iraq and Syria. Last September, Rubio actually wrote a letter to Obama saying it was his opinion that the president did not need congressional authorization for the fight. "Just as the U.S. has conducted operations against terrorists elsewhere, there is no legal reason preventing you from targeting ISIL in Syria," he wrote, using an alternate acronym for the group. He said he favored pursuing an international coalition, increasing air support and lethal assistance to Iraqi and Kurdish forces, destroying ISIS infrastructure and leadership, and supporting Syrian opposition forces.

Wisconsin Gov. Scott Walker (Republican): As a governor, Walker will have no involvement in the drafting or passage of an AUMF. He has shied away from getting specific about what is required to fight ISIS, saying, ""I wouldn't rule anything out," on ABC earlier this month, including being prepared to "prepared to put boots on the ground if that's what it takes."

New Jersey Gov. Chris Christie (Republican): Like Walker, Christie speaks in broad strokes when speaking about the conflict. He has blasted Obama's handling of the crisis, saying his administration underestimated the threat. But he has not called for as aggressive a response as some of his counterparts, saying during a trip to Iowa last weekend that stronger leadership doesn't necessarily mean "boots on the ground in every conflict," according to CNN.

Former Secretary of State Hillary Clinton (Democrat): Clinton and her husband, former President Bill Clinton, have both voiced support for the president's strategy to defeat ISIS, although Clinton has made it clear since stepping down as Secretary of State that she unsuccessfully advocated for arming moderate Syrian rebels. At an event in Chicago last October, Clinton predicted Congress would take some sort of legislative action on the issue, but did not explicitly call for an up-or-down congressional vote on the military campaign, according to the Washington Post.

Sen. Bernie Sanders, I-Vermont: The independent senator from Vermont has not yet committed to a position on the AUMF, although the topic came up at a Q&A earlier this week in Washington. Pressed on whether the president could possibly write an AUMF that he could support, Sanders declined to commit, saying he didn't want to "speculate without seeing the document," and seemed to suggest he was not inclined to favor an AUMF that included ground troops. He would only say, "I do not disagree with the air attacks that the United States is coordinating....What I just don't want to see is a ground presence and never ending war." Sanders would prefer to see more involvement from countries in the region, saying, " I think the United States and the Western world should be very supportive, but I think nations in that region are going to have to -- put some real skin in the game, more than they are right now."

Former Florida Governor Jeb Bush (Republican): Bush has not taken a position on the AUMF, but he is expected to take it up at a foreign policy speech he is delivering in Chicago next week.

CBS News Congressional Correspondent Nancy Cordes, Producer John Nolen and Associate Producer Donald Judd contributed to this report.