INDIANAPOLIS (AP) -- Barack Obama ended Republicans' 40-year grip on Indiana's electoral votes Tuesday with a narrow win over John McCain boosted by first-time voters, blacks, young people and voters worried about the economy, an Associated Press exit poll shows.

In becoming the first black elected president by defeating McCain, Obama also secured a place in history books as the first Democrat to win the state since Lyndon Johnson in 1964.

The AP exit poll showed that about a quarter of Indiana voters described themselves as independents and that more than half of them favored Obama over McCain. In 2004, about half of all self-described independents voted for Bush.

The president's low job-approval likely didn't help McCain. A slight majority of Indiana voters said that if McCain were elected president, he would continue Bush's policies.