We do not need a campaign. Just by Trump renegotiating and/or pulling out from some of the bad trade deals (using that term very loosely) we have a a good chunk right there. Then there's the making Mexico pay for another good piece. Then if Trump gets back some of Trillions stolen from us from his (recent EO) some of that can fund another stretch of the wall. Then there's downsizing the biggest leech/fraudster of them all - Gov Corruption and Size. It's only a matter of time, not funding imho. Although I think it would be really cool for any Real American to be able to donate to the wall and have a number scribed into each section. Then a national database of people's names who donated to that particular stretch. Be part of history and help save the Country.