Three factors, Santorum said, will determine his decision:

The first is whether he finds his message resonating in today’s political environment. He is traveling around the country — in early primary states like Iowa, New Hampshire and South Carolina — giving speeches and participating in town meetings. He said he’s “getting reaction from people on what they think of the message, what they think of the messenger, what they think of my background and my accomplishments and how that fits into what people are looking for in 2012.”

A second consideration is whether he can raise the money necessary for a serious effort. “You can’t run a campaign unless you have resources,” he said. “I’m talking to folks about what resources might be available if I do this.” He said a recently convened meeting with his former Senate staffers, reported on by a number of news outlets, was for him to relay these plans for 2012, solicit advice and gauge interest.

Lastly, there are personal considerations.