WASHINGTON » Proponents of sweeping immigration legislation on Tuesday will likely ignite a months-long battle between those who want citizenship for the nation’s 11 million illegal immigrants and opponents who view such an approach as amnesty.

A bipartisan group of eight senators plans to unveil legislation, drafted largely in secret, that would provide a 13-year-path to U.S. citizenship for illegal immigrants who arrived in the country before Dec. 31, 2011, but would demand that tougher border controls be in place first. The legislation is certain to unleash a torrent of attacks from Republican opponents on the immigration overhaul, similar to the kind of criticism that killed an effort supported by President George W. Bush in 2007.

The group plans to file the legislation Tuesday, but canceled its scheduled news conference because of the Boston Marathon bombing.

"We all met in the middle, knowing we would not please our entire constituencies, but the imperative of doing this is so important to the country that we had to get it done," said Sen. Charles E. Schumer, D-N.Y., a member of the bipartisan group. "Americans will be common-sense and fair to legal immigration and the 11 million who are here as long as they’re convinced there won’t be future waves of illegal immigration."

The biggest test will come for those Republicans who support the bill and will have to convince their skeptical Senate colleagues, constituents and grass-roots conservative base — not to mention Republicans in the House — that the legislation is not a reward for people who broke the law by entering the country illegally.

The bill requires that illegal immigrants wait a minimum of 10 years until they apply for legal permanent residence and an additional three years until full naturalization. It also mandates a series of rigorous enforcement measures, including at least $3 billion for the Department of Homeland Security to fortify border surveillance and apprehensions.

The department will have six months to present a plan to begin securing the border and identify where more border fencing might be required. No immigrants would be allowed to apply for "registered provisional immigrant" legal status — which would allow them to live and work here legally, as well as travel outside the country — until both plans are complete.

In order to apply for permanent resident visas, known as green cards, after 10 years, illegal immigrants would have to pay an approximate $2,000 penalty fee, including $500 upfront. They must also demonstrate knowledge of English and civics, and have worked regularly and maintained a continuous physical presence in the country.

In addition, agricultural workers and children brought to the country illegally by their parents — known as "Dreamers" — would receive an expedited path to legal status. (Both groups would be able to receive green cards in five years. The Dreamers would be eligible for citizenship immediately after they got their green cards).

The bill also creates a W-Visa program for lower-skilled workers, the outgrowth of a parallel negotiation between the country’s largest business and labor groups. A Bureau of Immigration and Labor Market Research, which is to be created by the bill, would be responsible for overseeing the number of workers who could come in annually.

The legislation also aims to eliminate the backlog of 4.7 million immigrants who have applied to come here legally and have been languishing while waiting for green cards. It creates a merit-based program for foreigners to become legal permanent residents, which focuses on both high- and low-work skills.

Tuesday’s legislation comes after months of delicate and fraught negotiations within the bipartisan group as well as a carefully managed public relations campaign that the senators hope will blunt any criticism before the expected attacks. Opponents of an immigration overhaul have been preparing to jump on what they see as objectionable sections of the legislation.

"We had to make compromises," said Sen. John McCain, R-Ariz., a member of the bipartisan group. "What really matters is most Americans agree with us that we need to address this issue in a comprehensive fashion. That was not true in 2007. I think that’s a very big difference."

In 2007, talk radio hosts and anti-immigration groups mobilized a campaign of angry phone calls to members of Congress that ultimately shut down the congressional switchboard. If Republican lawmakers hope to pass their bill in the Senate and get it through the Republican-controlled House, they will likely have to do more of the grunt work than their Democratic counterparts to bring voters and legislators on board.

Sen. Marco Rubio, R-Fla., another member of the group, has perhaps the most at risk. A Tea Party darling elected in 2010, his political aspirations are tied to the success of the legislation as well as to how his conservative base responds to his involvement in the bill.

This year, Rubio got a jump-start on an immigration tour when he appeared on conservative television and radio shows and reached out in phone calls and meetings to talk about the impending legislation. On Sunday, he pressed his case on five major network television programs as well as two Spanish-language networks.

The bill would allow an individual who qualifies for the new path to citizenship — but has been deported for noncriminal reasons — to re-enter the country as a "registered provisional immigrant," as long as the individual has a spouse or child who is a citizen or lawful permanent resident. Anyone in the country under the registered provisional immigrant status, however, would not be eligible for food stamps or other federal aid programs.

Under the new, merit-based visas, the legislation would gradually shift the emphasis from granting them based on family ties, toward visa approvals based on points awarded for an immigrant’s work skills, current employment, education and length of time in the United States.

In another border security measure, and a concession to the Republican members of the group, employers would be required to use an enhanced electronic verification system to make sure they are not employing anyone in the country illegally. Noncitizens would need to show a "biometric work authorization card" or "biometric green card."

Sen. Patrick J. Leahy, D-Vt., who leads the Senate Judiciary Committee, has scheduled two hearings on the bill — a response, in part, to Rubio, who has repeatedly called for public hearings.

© 2013 The New York Times Company