Lugar, a tea party target in 2012, is facing an extremely tough re-election bid from the right. His distinction is notable at a time when so many politicians are using a return to Constitutional values as their main platform point, and a strict constitutionalist would point to the need for a "declaration of war" before any military conflict.
Lugar is also demanding that the Arab League pay for the costs of a no-fly zone.
The White House hasn't stated whether the president supports a no-fly zone in Libya, only saying he is considering all options.
"We have ... led and coordinated an international response, the likes of which the world has never seen in such a short period of time," White House Press Secretary Jay Carney said Tuesday. "When it comes to considering military options, this president will always be mindful of what the mission -- should it be engaged -- what it entails, the risks that it poses to our men and women in uniform and its likelihood of having the kind of impact that we set out for it to have."
At a time when economy and jobs are at the forefront -- and when only 26 percent of Americans are optimistic about "our system of government and how well it works" -- observers say the president is wise to tread cautiously and see how the situation plays out before taking any bold steps.
"The problem for the president is that very few of the challenges he faces are easily fixed," Lindsay added. "What's happening in the Middle East reflects the tenions in those societies that have been supprressed for several decades. It is well beyond the capacity of this president or another U.S. president to be able to fix the problem."
ABC News' Z. Byron Wolf and Matthew Jaffe contributed to this report.