The Justice Department will sue the state of North Carolina for alleged racial discrimination over tough new voting rules, the latest effort by the Obama administration to fight back against a Supreme Court decision that struck down the most powerful part of the landmark Voting Rights Act and freed southern states from strict federal oversight of their elections.

North Carolina has a new law scaling back the period for early voting and imposing stringent voter identification requirements. It is among at least five Southern states adopting stricter voter ID and other election laws. The Justice Department on Aug. 22 sued Texas over the state's voter ID law and is seeking to intervene in a lawsuit over redistricting laws in Texas that minority groups consider to be discriminatory.

Republican lawmakers in southern states insist the new measures are needed to prevent voter fraud, though such crimes are infrequent. Democrats and civil rights groups argue the tough new laws are intended to make voting more difficult for minorities and students, voting groups that lean toward Democrats, in states with legacies of poll taxes and literacy tests.

Attorney General Eric Holder is expected to announce the lawsuit against North Carolina at a news conference Monday, according to a person who has been briefed on the department's plans but is not authorized to speak publicly about the matter and spoke only on condition of anonymity.

Holder will be joined at the news conference by the acting assistant attorney general for the Justice Department's civil rights division, Joceyln Samuels, and the three U.S. attorneys from North Carolina, the person said.

In the North Carolina lawsuit, the person said, the government will challenge requirements in state law that eliminate the first seven days of early voting opportunities and eliminate same-day voter registration during the early voting period. Same-day registration allows voters to cast a ballot immediately after presenting elections officials with proof of their name and home address.

The Justice Department challenge also is aimed at a provision eliminating the counting of certain types of provisional ballots by voters who cast ballots in their home counties but do not vote in the correct precincts.

Finally, the federal government will challenge a provision in the new law that requires voters to present government-issued identification at the polls in order to cast ballots. In North Carolina, a recent state board of elections survey found that hundreds of thousands of registered voters did not have a state-issued ID. Many of those voters are young, black, poor or elderly.

In remarks Sept. 20 to the Congressional Black Caucus, Holder said the Justice Department will not allow the Supreme Court's action to be interpreted as "open season" for states to pursue measures that suppress voting rights.

The Justice Department will ask a federal judge to place the four provisions in North Carolina's new law under federal scrutiny for an indeterminate period - a process known as pre-clearance. However, the provision of the Voting Rights Act that the Justice Department is invoking may be a difficult tool for the Obama administration to use.

A handful of jurisdictions have been subjected to pre-clearance, or advance approval, of election changes through the Civil Rights Act provision it is relying on, but a court first must find that a state or local government engaged in intentional discrimination under the Constitution's 14th or 15th amendments, or the jurisdiction has to admit to discrimination. Unlike other parts of the voting law, the discriminatory effect of an action is not enough to trigger court review.

Nowhere is the debate over voting rights is more heated than in Florida, where the chaotic recount in the disputed 2000 presidential race took place.

Florida election officials are set to resume an effort to remove noncitizens from the state's voting rolls. A purge last year ended in embarrassment after hundreds of American citizens, most of whom were black or Hispanic, were asked to prove their citizenship or risk losing their right to vote.

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AP reporter Michael J. Mishak contributed to this report.