States initially competed fiercely for the money, but that shifted after the 2010 midterm elections swept Republicans into power in Congress and in many statehouses. New Republican governors in Ohio and Wisconsin rejected hundreds of millions of dollars in federal aid that their states had won to build up their passenger rail systems.

Then Florida, which won $2.4 billion in federal money to build the nation’s first true high-speed rail system between Orlando and Tampa, sent back the money after its new Republican governor, Rick Scott, said it would be a boondoggle. Republicans in Congress have since blocked the Obama administration’s requests for more rail spending.

Against that backdrop, some rail advocates said it was a hopeful sign that some Republican presidential candidates have a history of supporting high-speed rail. “I hope that we can move past high-speed rail being a partisan issue — it certainly wasn’t always that way,” said Petra Todorovich, the director of America 2050, a branch of the Regional Plan Association, an independent urban research and advocacy group. “While politicians may differ over how to structure and manage high-speed rail, politicians on both sides of the aisle have recognized that there are certain corridors in the United States where this makes sense.”

Spokesmen for Mr. Gingrich and Mr. Perry did not respond to e-mails seeking comment about their views on rail. But Mr. Gingrich outlined his views in his 2008 book, “Real Change: From the World That Fails to the World That Works,” saying that the California, Florida and the Northeast Corridor from Boston to Washington are all “very conducive to this kind of high-speed train investment.”

But he does take a different tack from the Obama administration and many Democrats by arguing that development of rail has been stymied by “union work rules,” the inefficiency of Amtrak, politicians in Washington who subsidize uneconomic routes and “the regulations and litigation involved in large-scale construction in the United States.”

A spokesman for Mr. Paul, Jesse Benton, said in an e-mail that Mr. Paul “thinks high-speed rail is a very exciting idea and could be a very worthwhile project in many cases.”

Mr. Benton said that Mr. Paul believed that development of high-speed rail should ideally be left to the private sector, but that he would favor providing federal tax credits and rolling back regulations to promote its development. He said the letter Mr. Paul signed with other members of the Texas delegation in 2009 — which sought federal money for studies that it said would help “attract the large number of high quality private and public sector investors that will be key to making this project a success” — was an effort to ensure that “an equitable portion of the money was spent in Texas so Texan taxpayers received some of their money back.” That letter was first reported by Newsweek in an article in October about fiscal conservatives seeking federal spending for their districts.

But rail projects are still a tough sell with many conservatives these days, as Mr. Gingrich hinted in his 2009 remarks at the governors’ forum. “Let me just close with what I think is the central issue, that I’m prepared to debate both with liberals and conservatives, but probably I’m of somewhat greater value in debating it with conservatives,” he said, speaking of the need to change the federal financing process. “You can’t talk about American national security in the long run without a fundamental redevelopment of this country economically. It is not possible. And you can’t talk about a competitive American economy without a dramatically more robust and more modern infrastructure.”