There are several pharmaceutical companies that manufacture nicotine. I know from first-hand knowledge that at least one of those companies, who makes their own nicotine for their NRT products, is actively looking to capitalize on the e-cig market as another revenue stream (one that they feel may be larger than NRT in the near future).
I contend that NRT profits are a pittance compared to other, much higher margin, products. NRT patents expired long ago, and hence are now generic and OTC, so the margins are thin.
According to Reuters, in 2014, NRT grew 1.2% to $2.4B in sales worldwide (about $900M of that in the US). Realize that this total sales number is spread amongst many competitors, such as Pfizer, Novartis, and Actavis.
Compare that to a product like Humira, a single product sold by a single pharma company, with $11.5B in sales in 2013.
I have a hard time believing that pharma companies are spending a lot of money lobbying against e-cigs. I think their money would be better spent elsewhere, like dealing with Obamacare issues.