Last year’s It Boy of the graying Republican Party has been bigfooted by the GOP’s new twin heartthrobs, Sens. Marco Rubio of Florida and Rand Paul of Kentucky.

In conversations with scores of Republicans in Washington and beyond, it’s striking how little organic support or even interest there is for a Ryan presidential bid so soon after Mitt Romney elevated the Wisconsin wonk to the highest levels of national political stardom. Open-ended questions about who is drawing early attention don’t even include a pro forma mention of last year’s popular vice presidential nominee…

But his rapid fade speaks to what appears to be a shift in both the Republican Party and the broader political culture.

The GOP has for decades operated according to the rules of a sort of political primogeniture, nominating the next heir in line for the presidency every election cycle the contest is open. Primaries haven’t always held precisely to this tradition, but that somebody as popular within the party as Ryan is already being overshadowed suggests Republicans are changing in other important ways…

Ryan is actually hurt by having been on the ticket last year. Many Republican activists had heard of the smart young Wisconsin conservative but not actually seem him up close. And when they did, well, it didn’t send their pulses racing.

“He fell flat out here,” said Sam Clovis, a conservative talk radio show host in northwest Iowa. “He just didn’t measure up to the hype.”…

What isn’t likely to dissipate with time, though, is the taint on Ryan that comes with being a full-fledged congressional insider. There’s a growing desire on the part of Republicans to move away from the Washington wing of the party and the sort of austerity politics with which the congressional GOP has come to be defined.