More than a week after Barack Obama vowed to "close the deal" and wrap up the Democratic presidential nomination, he finds Hillary Clinton closing the gap and polls showing Americans still questioning his relationship with his controversial former pastor.

Clinton, still numerically outmatched when it comes to delegates won, is experiencing a surge in North Carolina and Indiana, which are holding primaries Tuesday and will set the trajectory for the campaign's final weeks.

An average of polls on RealClearPolitics.com shows Obama with a 7-point lead in North Carolina; last month he was carrying the state in some surveys by more than 20 points. And Indiana, a state that was thought to be neck-and-neck, is trending toward Clinton. Averages show her up by 6 points in the state.

Clinton was endorsed Friday by The Indianapolis Star, which circulates in the state's competitive capital suburbs. And a new Rasmussen Poll indicated that voters weren't accepting Obama's moves this week to denounce his former pastor, the Rev. Jeremiah Wright, and shed the controversy surrounding him.

Fifty-eight percent of those polled said Obama denounced Wright out of political convenience, not outrage. The poll was conducted nationally Wednesday and Thursday night.

"This primary election on Tuesday is a game-changer. This is going to make a huge difference going forward," Clinton said Friday in Kinston, N.C. "The entire country and probably the entire world is looking to see what North Carolina decides."

North Carolina and Indiana offer 115 and 72 delegates, respectively, representing Obama's last one-day chance to pull away in the delegate count and leave Clinton in the dust. The six contests that will remain after Tuesday each offer fewer than 60 delegates, and individually are unlikely to have a big impact on the dynamic of the race.

Asked about his apparent rut at a press conference in Indianapolis Friday, Obama tried to find the silver lining.

"We have had a rough couple of weeks; I won't deny that," he said. "And what's remarkable is that, despite that, we are seeing terrific support all across Indiana and all across North Carolina. I have been incredibly encouraged over the last several days as we have campaigned. ...

"This campaign has been tight throughout. But I am very confident that the American people are looking for the kind of truth-telling and serious policy-making that is going to have an impact on their lives. And as long as I am talking about the issues that matter to them, I think we have a terrific chance," he said.

Obama's nearly 10-point loss in Pennsylvania on April 22 made a set of victories Tuesday all the more important for him. He would like to shake Clinton and send a signal to uncommitted superdelegates that he's the Democrat with the mandate from voters.

Clinton needs those superdelegates to overcome Obama's total delegate lead, which as of Friday was 1,736 to 1,602.

In the past two months, Obama has whittled Clinton's superdelegate lead by half. Clinton holds a 20-superdelegate lead, 268 to 248.

One notable superdelegate, former Democratic National Committee Chairman Joe Andrew, switched his support from Clinton to Obama on Thursday, despite having been named to the top party job by former President Bill Clinton.

"This has got to come to an end," Andrew said from his hometown of Indianapolis. He said he planned to call all the other superdelegates he knows and encourage them to back Obama.

Obama also got the backing Friday of former DNC Chairman Paul Kirk Jr., who said in a statement: "Senator Obama is the one candidate who has and will continue to expand the electorate beyond the traditional Democratic party base and bring young and new and independent voters to the Democratic banner in November, an essential ingredient to a Democratic victory. ...

"After the attention paid to the poisonous and polarizing diatribe of recent days, Senator Obama's clear and compelling message, which appeals to our best instincts as Americans, is more important than ever."

Clinton's campaign brushed off Kirk's endorsement as "old news."

FOX News' Aaron Bruns and Bonney Kapp and The Associated Press contributed to this report.