This is a new poll, just announced in South Bend. Here the link South Bend Tribune Statewide Poll of Democrats. Among whites it is Clinton 55, Obama 40; among blacks Obama 81, Clinton 16. Men: Obama 50, Clinton 43; Women Clinton 54 and Obama 43. Here is a PDF with much more detailed information.
400 likely Democratic voters, but margin of error is 5%, Research 2000 did the polling. The voters were interviewed statewide by telephone from March 31 through April 2, 2008.