WASHINGTON » Andy Welsh of Portland, Ore., was so enthusiastic about President Barack Obama’s first run for the White House that he voted absentee while spending a semester abroad in Spain. But Welsh, now 26 and an aspiring diplomat, said the gridlock in Washington has been "a real bummer ever since."

Katie Hermann, 29, a corporate strategist in Chicago, also supported Obama for president, but when she thinks about the state of politics in America today, she said, "I feel slightly more discouraged than I did back when President Obama was first elected."

David Durgin, 28, who is putting himself through the University of Colorado and owns a car detailing shop near Denver, did not vote for Obama and has also soured on Washington. "There’s too much fighting going on between the parties," he said.

These three voters — Welsh, a registered independent; Hermann, a Democrat; and Durgin, a Republican — reflect what political analysts see as a troubling trend: The idealism of youth is slipping away, replaced by mistrust and a growing partisan divide among voters younger than 30. These "millennials," who turned out in droves to elect Obama in 2008, are increasingly turned off by politics. Experts fear their cynicism may become permanent.

"If you are 24 years old, all you know is petty partisan politics while big issues aren’t getting addressed, while the economy is still struggling," said Trey Grayson, director of the Institute of Politics at Harvard University, which on Tuesday will release the results of the latest in a series of polls documenting millennials’ attitudes toward government. "So you wonder whether the governing institutions of your country are up to the task."

The Harvard survey, of more than 3,100 voters younger than 30, found that faith in most major institutions — with the notable exception of the military — has declined over the past several years. Today, only 39 percent of young voters trust the president to do the right thing, as opposed to 44 percent in 2010. Just 18 percent of voters younger than 30 trust Congress, compared with 25 percent in February 2010.

"The hyperpartisan and gridlock that has befallen Washington, D.C. ,is having a traumatic effect not just on our nation’s status at home and abroad, but on the political health of tens of millions of once (and hopefully future) idealistic young people," John Della Volpe, the Harvard institute’s polling director, wrote in the study’s conclusion.

The economy is a major reason for the disillusionment of young voters, who are saddled with student debt and worried about how to find jobs, said Kristen Soltis Anderson, who tracks young voters for the Winston Group, which advises Republican candidates. Durgin is one example; part of his upset with Washington, he said, has to do with his livelihood.

"I’m losing money," he said, adding, "There’s nothing positive that has happened to me in the last 12 months."

Young voters seem disappointed with both political parties, although Anderson, the Republican pollster, said her party appears to be taking the brunt of millennials’ dissatisfaction. Obama had a 52 percent approval rating in the Harvard poll — slightly better than his approval ratings in polls of older adults nationwide — but down from his approval rating of 58 percent in a Harvard poll of millennials in 2009.

"They are disappointed with him, yet many question the motives of Republicans even more," Anderson said.

She added: "It’s tough to be young these days — the economic concerns are very great, and a lot of what you hear out of Washington is not addressing those concerns. There are a lot of questions: Does either party really have my best interest at heart? And I think the answer to that is, ‘No."’

That cynicism is coupled with a deepening partisan divide. While Obama’s job performance rating would suggest that most young voters feel he is doing well in office, a deeper look at the numbers reveals a split: 86 percent of young Democrats approve of Obama’s job performance, while only 10 percent of young Republicans do.

"At no time since President Obama was elected in 2008 have we reported less trust, more cynicism and more partisanship among young voters," Della Volpe wrote in the study. "Young voters, like older Americans, are becoming more partisan by the day."

The split is also evident in issues like gun control, immigration and government spending, where young voters are more likely today than several years ago to adopt the views of their own parties. The Harvard survey found that the percentage of young Democrats who want stricter gun laws rose 8 points from 2010. But the percentage of Republicans who want stricter laws declined by points.

Political analysts know that voters are heavily influenced by the president and the political climate in which they come of age; young voters of the Franklin D. Roosevelt era, for instance, tended to stay Democratic throughout their lives, while those of the Ronald Reagan era still tilt strongly Republican.

Grayson, the Harvard institute director, said experts there worry that the lasting effect on this generation of voters will be that their cynicism about government and politics will turn into "a negative attachment that may be hard to overcome."

Welsh, of Oregon, who is working as a hotel desk attendant while studying for the State Department’s examination to become a foreign service officer, may offer a hint of that sentiment. He still approves of Obama, he said, but he has little use for other politicians in Washington. "I just don’t trust them," he said.

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