INDIANAPOLIS (AP) — Young Indiana voters, including many who voted Tuesday for the first time, helped Barack Obama come close to defeating Hillary Rodham Clinton in the state's Democratic presidential primary, exit polls show.

Nearly one in five people who cast votes in the Democratic primary were under age 30, with most — six in 10 — favoring Obama, according to exit polls with nearly 1,900 voters who were part of Tuesday's record turnout.

The Illinois senator has successfully courted the college-age electorate in other states and that tactic paid off again in Indiana, where his campaign targeted college students with voter registration and early voting drives.

"They favored Obama overwhelmingly," said Robert Schmuhl, a professor of American studies at the University of Notre Dame.

Obama wooed Indiana University's more than 37,000 students on the Bloomington campus, sponsoring a free Dave Matthews concert that doubled as a voter drive. He made two visits to Bloomington, taking part in Little 500 festivities and dropping by Nick's English Hut, a popular student hangout.

Most notably, Schmuhl said Obama's campaign and his supporters have employed the technology favored by young people — cell phones, text-messaging and social networking sites like Facebook and MySpace — to help drum up support and money for him.

"When the history of the 2008 campaign is written we're going to discover that the Obama campaign broke new ground in a number of different areas, including fundraising and delivering messages to various groups," he said.

While Clinton won 83 of Indiana's 92 counties, Obama won the state's most populous counties — Marion, Lake and Allen counties — as well as those with big college populations. He won Monroe County, home of IU, Tippecanoe County, where Purdue University is located, and St. Joseph County, the home of the University of Notre Dame.

The college vote, along with Obama's strong support among Indiana blacks — nine of 10 of whom voted for him — combined with college graduates and liberal voters to give him a better Indiana performance than had been predicted, Schmuhl said.

"They went to the groups that would provide support, and it paid off," he said. "He turned them out a little better than people had expected and here we are today talking about when Hillary might get out of the race."

Although Obama played to his core groups, Clinton captured hers as well — winning the votes of two-thirds of working-class whites in Indiana, while also drawing in older people and whites overall to claim the win with 51 percent of the vote.

Robert Dion, a professor of American politics at the University of Evansville, said coming into Indiana's primary contest, political observers had expected a Hoosier outcome similar to the results in Ohio and Pennsylvania, which also have a large number of blue-collar voters.

In those two states, the former first lady won by significant margins.

But Dion said Indiana favored Obama because Indiana's population isn't quite as old as Pennsylvania's and Indiana's economy is not as bad off as Ohio's. Many Hoosiers are also familiar with Obama because the state abuts Illinois, he said.

"People know him up and down the whole western side of Indiana, so that gave him a cushion I think. Up until yesterday, he had never lost a state that bordered Illinois, and he came close to winning," Dion said.

The exit polling results were prepared by Edison Media Research and Mitofsky International for The Associated Press and television networks. There were 1,881 voters in the Indiana Democratic primary who were interviewed, for a margin of sampling error of plus or minus 3 percentage points.