Other potential options include training and assisting local forces, recruiting help from other countries and establishing a no-fly zone or safe zone for refugees.
The options are part of the so-called Plan B should the ceasefire that takes effect this weekend falls apart, the official said.
So far, "Plan B" is more an idea than a specific course of action and nothing has yet been agreed to, several administration officials said.
Special Forces could be used for more counterterrorism operations, as well as increase work with moderate opposition forces on the ground.
Military options could also include increasing the training, advising and assisting of moderate forces. U.S. intelligence agencies and other countries could be called upon to help provide arms and assistance, the official said, again emphasizing that no decisions have yet been made.
National security officials continue to look at the option of a no-fly zone or safe zone for refugees and displaced persons, the official said. However, the Obama administration, led by the Pentagon, still feels such a plan would be too costly and resource-intensive, the official said.
And it's been made more complicated by the presence of Russian air-defense radars and missiles that now cover a large part of Syria.
"I can't tell you it's off the table," the senior official said. "It's at the edge of the table, but not off it."
Secretary of State John Kerry addressed the possibility in testimony before Congress this week.
"Our Pentagon estimates that to have a true safe zone in the north of the country, you may have upwards of 15,000 to 30,000 troops. Now, are we ready to authorize that? Are we ready to put them on the ground?" he asked.
He added, "It really requires Congress to sort of analyze if somebody's going to call for a no-fly zone. It takes planes going out and destroying the air-defense system so you can fly around and make it a no-fly zone."
To further ratchet up the pressure on ISIS, Kerry also raised the prospect that the United States would publicly declare ISIS had engaged in genocide by persecuting people on the basis of their religion.
"There is a process ongoing right now making an analysis under the law," Kerry told Congress. "I have to make this judgment, and I am prepared to make it and make it soon."