Well, let's look at how realistic his plan is. This is a technical forum after all
Moon base means a Moon landing, so Newt's plan is essentially Moon by 2020, or, more likely, Moon by 20 July 2019 for propaganda reasons. So that's 6.5 years after assuming office. No way this can be done using the private sector. That would require Apollo-style, NASA-led effort.
As the adage goes, we need a Booster, a Capsule and a Lander. Money for the Booster (SLS) and Capsule (Orion CEV) is already appropriated. In fact,
wiki page on SLS says that unmanned SLS/CEV lunar flyby is projected December 2017. That's 18 months before the cutoff date, and it could probably be shortened by 6-12 months. So we need a lander. Since SLS/CEV is essentially CxP hardware, then the logical move is to resurrect Altair LSAM.
This, I believe is the crucial point here. If he's elected and wants to do this, he has to restart Altair; if he won't, it means he is not serious.
Now, the problem here is that there is no money for Altair. Worse yet: this program would require developing Altair
in parallel with SLS/CEV, which is exactly the thing that present administration wanted to avoid. (The whole Flexible Path idea; do the asteroid mission which does not require a lander, and then build a lander). At the same time, he wants to give 10% of NASA money for prizes. So a logical thing to do, would be to cut NASA science and R&D (basically, anything that is not directly related to the Moon and can get axed, gets axed) and use that money for Altair. And surface systems. (Although I believe CxP managed to build some of these before they were closed.) The weak point here is getting the Congress to change appropriations. On the other hand, an average voter has no idea what NASA
really does, while a Moon base is something tangible, so he could get support for this idea.
And there's another elephant in the room, which is the ISS. Because of international obligations, he would have to keep the ISS flying until 2020. So that means doing the Moon program in parallel with keeping ISS afloat. That's what even the Constellation wanted to avoid, by downing the ISS in 2016, to free money for the Moon! But 2016 ISS deorbit is no longer an option.
Bottom line: I believe this could be pulled, but it would wreak
massive havoc in other NASA projects.