The Federal DOT's
List of Designated HSR Corridors, cover something like 34 states already. That would be 68 out of 100 Senators, if things were as simple as that.
mind you having a 3 tiered plan makes a lot of sense anyway, Senators or not. It would be kind of silly to have HSR corridors with nothing connecting them to secondary population centers other than roads.
Thi is an incredibly disconnected map in every sense of the word. It is a compilation of the dreams of various pressure groups, not the result of an analysis of real potential traffic.
I know. It has its weirdness undoubtedly resulting from the political process that went into putting it together. But again purely from the political process perspective, such as it is, one of the first steps of getting grants for HSR is for the corridor to be designated an HSR Corridor. Not saying this is the right way to do things. But at present that is the way it is.
There is another more interesting map that I have come across, that is provided by the USHSRA which can bee seen
here. It has an interestingly timeline in 5 year steps.
Even that has some seemingly impractical oddities. Just to take one example, it proposes that there be two totally separate HSR lines, one from Washington DC to Pittsburgh and another from Philadelphia to Pittsburgh, i.e. two HSR lines through mountains, when the trans mountain portion could be consolidated into a single segment by doing it in the following three segments, roughly speaking - (i) Washington - Lewistown (vicinity), Philly - Lewistown (vicinity), Lewistown (vicinity) - Pittsburgh, assuming that the Juniata alignment is still the desirable one for HSR. Why would one want to plan two trans mountain segments when one would suffice with relatively small time penalty, beats me.