The race for the Democratic presidential nomination is tighter than ever in Indiana, but a new exclusive WSBT-South Bend Tribune poll shows there are some changes.

Hillary Clinton and Barack Obama are still in a dead heat, but this latest poll also looks at who has the best chance to take on John McCain in the fall.

The most noticeable difference is that Barack Obama now has a slight lead over Hillary Clinton. Obama has 48 percent of the vote to Clinton's 47 percent. It was the opposite three weeks ago. Obama's lead still falls within the margin of error.

Pollster Del Ali says the results don't signal a clear victory for either candidate.

"Neither candidate has a decisive advantage. Neither candidate has hit that 50 percent plus 1 plateau — the magic number to say it's their race to lose," he said.

As in the past poll, there are relatively few undecided voters to sway. Despite that, both campaigns say they're encouraged by these results.

"I'm encouraged that both Sen. Clinton and Sen. Obama are coming into the final two weeks dead even for all practical purposes," said Joe Hogsett with the Clinton campaign.

"I think that it's going to be real tight and every single vote will count. We're going to be making a case to the people of Indiana that Sen. Obama is the person to fundamentally change Washington," said Kevin Griffis with the Obama campaign.

Looking ahead to November, our poll shows John McCain would beat either Democrat. If the election were held today, 51 percent of those surveyed said they would vote for McCain, 43 percent for Obama.

The numbers are similar if Clinton was the candidate: 52 percent for McCain, 41 percent for Clinton.

Political science expert Elizabeth Bennion from Indiana University South Bend says the key to victory in November is voters who don't identify with a particular party.

"They need to convince people to vote in the Democratic primary and for the general election, whoever gets the nomination will need to convince voters that they are independent thinking. That they address the issues that voters care most about," she said.

The top issues in this poll are the economy and taxes. Iraq has dropped to third place.

Bennion expects to see more negative ads in the coming weeks. Voters in this poll say they think Clinton is running a more negative campaign. Bennion says that's a challenge for Obama who has been trying to stay above the fray.

She says if he becomes equally negative, that could actually help Clinton.

For more on the poll, read Friday's South Bend Tribune.

For more election headlines and voter resources, go to WSBT.com's Campaign ‘08 section.