The same way you get Kansas senators to support spending money on LA subways, or Hawai'i senators to support spending money on the Interstate Highway system, or Idaho senators to spend money on the Intracoastal Waterway, all of which also involve their constituents gaining almost nothing from spending but having to pay for it anyway. You roll the spending into omnibus bills covering not just passenger rail but other forms of transportation or other spending priorities so that opposing it is a self-own for them, remind them that opposing bills helping these states mean those states will oppose bills helping them, and include sweeteners geared towards giving them something of a benefit without actually having a line through them (e.g., maybe you won't have a line in Utah, but they might have a factory for building trains). You can, in fact, see all of these factors at work in the last attempt at federal spending on high-speed rail, under the American Recovery and Reinvestment Act of 2009. This was a big omnibus bill that included not just spending on high-speed rail but a range of other measures intended to help the economy, thereby making sure that every state got something from passing the bill. Naturally, this meant that there was no incentive for the senators from Idaho (or, more realistically, Minnesota, for reasons I will get to) to oppose the bill just because part of it was spending money on something that wouldn't benefit them, and made sure that the senators from Hawai'i knew that trying to shut that down would just mean retaliation from California, New York, and so on. And it gave out grants to all sorts of states, even for routes that perhaps didn't make a lot of sense, so that more states than just the "sensible" options would get something. Thus, there wasn't really all that much difficulty in getting it through. Certainly very little opposition based on geography. Which gets to another point: Geography isn't destiny. Geography isn't even important. Opposition to high-speed rail in the United States has nothing to do with whether a state will see benefits from it or not, but whether you are Republican or not, which is why Texas, despite having an excellent potential for high-speed rail, was opposed to the whole thing, voted against ARRA, and barely bothered trying to get any money to study high-speed rail, and why Scott Walker, John Kasich, and Rick Scott canceled high-speed rail projects despite their states actually having good prospects for high-speed rail and it offering clear benefits for them. Conversely, states like Hawai'i and New Mexico, despite seeing little potential benefit from high-speed rail and not actually getting any grants, voted in favor and supported the idea. EDIT: This, on the other hand, is a serious issue. Cost is a problem...but it's a problem that affects everything, not just passenger rail, so it points to a deeper issue in public procurement. Other countries can do this for much more reasonable amounts of money, despite being just as unionized (France), just as protective of private property (Japan), just as this and just as that, whatever excuses you can come up with. If you want gory details, you could read this report written by Deutsche Bahn on CAHSR capital costs, and if you want solutions Alon Levy is always a good start.