The battle over legislative districts in North Carolina has forced the state Board of Elections to call off the May 7 primary elections, potentially upending state legislature and U.S. congressional races.

The decision means the race to succeed retiring Republican Sen. Jesse Helms and determine 13 congressional contests will be postponed at least several weeks.

"My feeling is, if we try to set a date now, not knowing what the Supreme Court is going to do with the legislative races, we would be asking for trouble," said board member Chuck Winfree.

The state Supreme Court had issued an injunction last Thursday to halt the state House and Senate primaries, following a lower court's ruling that newly drawn legislative districts are unconstitutional.

The election board's unanimous vote to delay the primaries was based on concerns about stifling voter turnout and adding to state and municipal expenses by having multiple primaries.

Multiple primaries were tried before, and failed miserably when only 7 percent of voters turned out to select U.S. House candidates in 1998.

State officials say the cost of holding another election for legislative races could cost an additional $1.7 million and the debt would fall to county governments.

The Supreme Court is scheduled to hear arguments April 4 in a lawsuit brought by Republican lawmakers challenging new legislative districts. Republicans argue that the new congressional districts were unconstitutionally drawn by state legislative leaders attempting to create favorable boundaries in spite of a state ban splitting counties.

Democrats contend federal protections for minority voters and proportional representation have essentially invalidated the state ban on splitting counties.

Last month, Superior Court Judge Knox Jenkins sided with the Republicans, saying the federal requirements didn't mean lawmakers could simply ignore the state constitution.

In his ruling, Jenkins left it up to the state's appellate courts to decide whether to delay upcoming primaries by staying his own order.

If the Supreme Court sides with Democrats, the state elections board will need five weeks to print ballots and allow absentee voters to send in their votes, State Elections Director Gary Bartlett said.

If the Supreme Court sides with Republicans, the redistricting commission will have to go back to the books and remap the boundaries. Lawmakers will then have to get clearance from the U.S. Justice Department saying that the new lines don't violate the Voting Rights Act, and the state would then have to reopen the filing period for candidates. 

The process could delay the primaries until September or later since state lawyers say if they lose they will ask the U.S. Supreme Court to hear the case.

All sides agree that postponing the primaries was the necessary thing to do.

"Clearly, they did the right thing. I'm very pleased they were unanimous in their decision," said Bill Cobey, head of the state Republican Party. 

"I think it was probably a prudent decision for the board to make," said Scott Falmlen, executive director of the state Democratic Party.

U.S. Senate candidate Elaine Marshall, a Democrat, said moving the election from its traditional date will hurt turnout, but not as much as dividing primaries. She said she's also pleased the election board took into account the additional costs "with the budget situation being what it is."

The Associated Press contributed to this report.