Therein lies his paradox. To gain stature — and attract enough donors to be competitive in the first four make-or-break contests — Rubio needs to aggressively promote himself, but not so aggressively that he becomes a focal point of the race.

The think-small strategy isn’t just a matter of dodging incoming fire: Another person close to the campaign said that Rubio had counted on more cash early on — but opted to steer much of his war chest to travel, in the belief that the energetic, articulate candidate would be the campaign’s best kick-starter. That means small operations in battleground states and a focus on relatively cheap social media and volunteer recruitment.

“If you are still standing in May, running smaller or leaner now is going to look very smart. If you are out, not so much,” says Chip Felkel, a South Carolina GOP consultant who is skeptical of Rubio’s decision. “Rubio’s team has prided themselves on this lean approach, and on their commitment to digital rather than boots on the ground. They are making a pretty gutsy bet that you don’t need a presence anywhere except online. That may make your campaign more agile, sure, but I am not sure that equates to strength.”