US lawmakers return from the midterm elections this week determined to give President Barack Obama the money and authority he says he needs to battle the Islamic State (IS) in Iraq and Syria.

Congress is expected to quickly approve the president's request for an extra $5.6 billion, while beginning to lay the groundwork for a new Authorization for Use of Military Force (AUMF). While less divisive than the effort to oust Iraqi President Saddam Hussein a decade ago, the debate remains controversial on Capitol Hill, where lawmakers of both parties are deeply skeptical that the Obama administration has a plan for victory.

"I remain concerned that the President’s strategy to defeat [IS] is insufficient," House Armed Services Chairman Buck McKeon, R-Calif., said in a statement Nov. 7 following the administration's announcement that it was authorizing sending up to 1,500 more troops to Iraq. "I would urge the President to reconsider his strategy and clearly explain how this additional funding supports a new direction. Such clarity is more likely to find swift Congressional approval."

McKeon's panel will hold a hearing Thursday on the administration's "Strategy and Military Campaign against Islamic State." Witnesses include Defense Secretary Chuck Hagel and Joint Chiefs Chairman Martin Dempsey.