RALEIGH, N.C. (AP) — Not since 1988 has North Carolina had much of a voice in choosing a presidential nominee. Back then, it joined several Southern states to help pick Al Gore, a neighbor from Tennessee.

But the longer-than-expected race between Hillary Rodham Clinton and Barack Obama for the Democratic presidential nomination will thrust the state into the national spotlight when it has its say May 6. Indiana also votes that day.

The primary, offering 115 national convention delegates, comes two weeks after Pennsylvania gave the former first lady the win she needed to stay in the race. But Obama is favored to win North Carolina, the largest prize among the contests remaining.

“My crystal ball wasn’t working well last year, and I certainly would not have anticipated this,” said state Democratic Party chairman Jerry Meek. “But, in retrospect, having a May primary was a tremendously astute decision.”

Voters, especially new ones, have taken note.

More than 165,000 people have registered to vote in North Carolina in the first three months of the year, a nearly threefold increase from the same period in 2004. Election officials expect a record turnout May 6 — about half of the more than 5.7 million registered voters, compared with past turnouts ranging from 16 percent to 31 percent.

Another wild card: A new law allows unregistered voters to sign up and vote on the same day through May 3. Both campaigns have launched efforts to turn out those voters, and the polling sites have been flooded since they opened last week.

As of Thursday morning, more than 81,000 “one-stop” ballots had been cast — about eight times higher than during the 2006 primary, according to the state Board of Elections. An additional 8,700 absentee ballots have been collected, officials said.

Voter registration is up overall, but the biggest boost has been among blacks.

More than 45,000 black voters have registered in the first three months of 2008, compared with just over 11,000 in the same period four years ago. Blacks make up more than 20 percent of the state’s registered voters, according to Board of Elections data.

Those numbers bode well for Obama, who has won strong black support throughout the primaries.

There are other signs Clinton will have a hard time achieving victory in North Carolina.

Neither of the state’s top two Democrats, outgoing Gov. Mike Easley and former White House hopeful John Edwards, have endorsed a candidate. Among superdelegates who have made their choice known, Obama has a 6-1 edge. The 10 remaining superdelegates, including Meek, are uncommitted.

The two Democratic candidates vying to replace Easley, who is barred by law from seeking a third consecutive term, are not only backing Obama but have made their support for him a feature of their campaigns.

State Treasurer Richard Moore has run radio ads on stations popular with black listeners noting he “was the first Democrat running for governor to endorse Barack Obama for president.” His rival, Lt. Gov. Beverly Perdue, has sent mailers to likely black voters with a photo of her with Obama.