High gas prices and the changing habits of young people are driving a shift toward mass transit that could influence federal and state budget battles.

Nationwide last year, buses, subways and trains had their second-highest ridership since 1957 – behind only 2008, when the price of gas topped $4 a gallon.

Amtrak last week said it carried 3.7 percent more passengers in the six months ending in March than in the same period a year earlier. It appears headed for its ninth national ridership record in 10 years.

U.S. highway use fell slightly in 2011, with 1.2 percent fewer vehicle miles traveled than in 2010.

In a March national poll by the AAA auto club, 14 percent of motorists said they were using public transit more often because of high gas prices, and 23 percent said they would in the future if prices stayed high.