In a move certain to escalate the legal tug of war over illegal immigration, state lawmakers from across the country announced Wednesday that they are launching an effort to deny automatic citizenship to the U.S.-born children of undocumented immigrants.

Republicans from Pennsylvania, Arizona, Oklahoma, Georgia, South Carolina and other states said they were taking aim at birthright citizenship by seeking to apply the Constitution’s 14th Amendment — which grants citizenship to all children born in the United States — only to children with at least one parent who is a permanent resident or citizen.

Within weeks, several state legislatures are expected to introduce bills that would lay the groundwork for such a reinterpretation of the 14th Amendment, which was passed in the wake of the Civil War in order to confer citizenship on freed African American slaves.

Proponents said their strategy is designed to draw legal challenges and get the issue before the Supreme Court.

Civil rights groups denounced the move and said it was motivated by racism against Latino immigrants. They also said that Supreme Court precedents have made clear for more than a century that the 14th Amendment applies to all children born in the United States, regardless of whether their parents were in the country legally.

About 340,000 children were born in the United States to undocumented immigrants in 2008, according to a study released in August by the Pew Hispanic Center. Thousands of children born to tourists and foreign students also could be denied citizenship if the 14th Amendment were reinterpreted.

The move is the latest example of states testing the boundaries of federal control over immigration. “This country has a malady, and it is costing her citizens dearly,” said South Carolina State Sen. Danny Verdin (R). He added that the rise in number of what he called “anchor babies” — children born in the United States to undocumented immigrants — had created a huge problem.

Pennsylvania State Rep. Daryl Metcalfe (R) said that he was planning to introduce legislation within weeks and that legislators in about 40 states, including Virginia, had signed up to learn more about the proposal. Metcalfe said he expected about 20 states to introduce legislation soon, among them Pennsylvania, Arizona, Nebraska, Alabama, Delaware, Idaho, Indiana, Michigan, Mississippi, Montana, New Hampshire, Oklahoma, Texas and Utah.

Corey Stewart, chairman of the Prince William County Board of County Supervisors, who has been pushing for Arizona-type legislation in Virginia, said he is disappointed that Virginia is not in the vanguard of the push to end birthright citizenship.

“It has been so difficult to get bold action,” he said.

In Maryland, Del. Patrick L. McDonough (R-Baltimore County), the legislature’s most outspoken critic of illegal immigration, said it is possible he may introduce birthright legislation. But it is unlikely to advance very far in a state controlled by Democrats.

“It’s hard to imagine a more quintessentially anti-American proposal than one that would judge a person by their parents or grandparents or great-grandparents,” said Lucas Guttentag, who directs the Immigrant Rights Project at the American Civil Liberties Union. Guttentag said that the ACLU would counter any effort to challenge the 14th Amendment.

Proponents of the new strategy said they would adopt a two-pronged approach. The first is to introduce bills in state legislatures that revive the concept of “state citizenship.” Only children with at least one parent who is a U.S. permanent resident or citizen would be granted state citizenship, though it wouldn’t prevent the federal government from granting U.S. citizenship to the children of undocumented immigrants.

The second prong of the strategy involves a more direct challenge to the authority of the federal government by using what is known as a state compact to draw a distinction between the children of undocumented immigrants and those of legal permanent residents and U.S. citizens.

A compact is a legal term that describes a measure, passed by states, that requires congressional approval. If Congress approves a state compact, it can become federal law without requiring the signature of the president, said Kris Kobach, professor of law at the University of Missouri at Kansas City and the Kansas secretary of state-elect.

The states involved in the compact would issue different birth certificates to children of permanent residents and U.S. citizens from those of undocumented immigrants, tourists and foreign students. The birth certificates would draw a distinction between those children whose parents are “subject to the jurisdiction of the United States” — a phrase from the 14th Amendment — and other children whose parents are not.

Kobach and other proponents said that because undocumented immigrants are in the country illegally, they are not under the jurisdiction of the United States.

Effectively, states would be throwing down the gauntlet to Congress to deny citizenship to children who do not have at least one parent who is a permanent resident or a citizen.

Walter Dellinger, who was assistant attorney general and acting solicitor general in President Bill Clinton’s administration, predicted that the Supreme Court would dismiss the challenge to the 14th Amendment because of past decisions that ruled children born in the United States were citizens.

In 1898, the Supreme Court ruled that children born to Chinese migrants — who were themselves barred by exclusionary racial laws from becoming citizens — were U.S. citizens since they were born on U.S. soil.

The clause in the 14th Amendment that restricted birthright citizenship to those “under the jurisdiction of the United States,” he added, merely excluded the children of foreign diplomats from becoming citizens.

Repeated challenges to the 14th Amendment, several civil rights experts said, had questioned the legitimacy of African American, Chinese American and Japanese American citizens. Each time, the challenge was refuted.

“This matter has been raised in every instance in a racial context,” Dellinger said. “That’s why we wanted a simple rule: Every new girl or boy born in this country is simply, indisputably, an American.”

Staff writers Anita Kumar, Rosalind S. Helderman and John Wagner contributed to this report.