“Young people absolutely believe that there’s a role for government,” said Matt Singer, a founder of Forward Montana, a left-leaning though officially nonpartisan group that seeks to engage young people in politics. “At the same time, this is not a generation of socialists. They are highly entrepreneurial, and know that some of what it takes to create an environment where they can do their own exciting, creative things is having basic systems that work.”

Here in Montana, a state that backed John McCain in 2008 and Mr. Romney last year, voters under 30 have helped elect two Democratic senators and a new Democratic governor. Nationally, young voters have since 2004 been casting their ballots for Democrats by far wider margins than previous young generations — a shift that could reshape American politics for decades.

Under-30 voters are “the only age group in which a majority said the government should do more to fix problems,” the nonpartisan Pew Research Center reported in November. In a Pew survey a year earlier, more than 8 in 10 said they believed that Social Security and Medicare had been good for the country, and they were especially supportive of seeing the programs overhauled so they would be intact when they retire. (Young people were also more open than their elders to privatizing the programs.)

And while Washington fights about how to cut the federal deficit, young voters believe that it is more important to create jobs, have affordable access to health care and develop “a world-class education system,” according to the Institute of Politics at Harvard.

Those sentiments were borne out in interviews here. When Forward Montana convened a focus group at a Missoula cafe to develop a “youth agenda” last week, the deficit did not register a mention. One attendee, Michael Graef, an 18-year-old who started a fitness business rather than attend college, said he rarely thought about the deficit.