By Richard Cowan
WASHINGTON (Reuters) - A bipartisan group of senators on Wednesday began trying to sell a freshly written, 844-page immigration bill knowing that changes will be made but vowing to protect the pillars of what they hope will become a landmark law.
The ambitious plan, to give legal status to around 11 million illegal immigrants, already has won some powerful backing.
Senate Majority Leader Harry Reid, a Democrat, on Wednesday called it a "very strong bill," promising, "I will do everything in my power to get this legislation across the finish line."
Reid's endorsement came on the heels of President Barack Obama's embrace of the bill on Tuesday, even before the eight Democratic and Republican authors posted it online hours later.
The bill was greeted skeptically by some conservatives, however, arguing among other things that it could be too costly, a theme which has gained traction among Tea Party groups across the country. Some Tea Party activists organized a protest Tuesday at one of Florida offices of Republican Senator Marco Rubio, one of the bill's sponsors who was elected with Tea Party support.
Lawmakers, lobbyists and immigration groups girded for a long, tough fight that is expected to extend at least through the summer and with no guarantees of success on the bill that would also make it easier for industry, particularly high-tech industry and agriculture, to hire workers from abroad.
The sales job on the legislation, "Border Security, Economic Opportunity and Immigration Modernization Act of 2013," began in earnest on Wednesday in a room on the second floor of the U.S. Capitol, just off the Senate chamber.
Sixteen Democratic senators met with immigration groups, labor union officials, civil rights activists, civil liberties organizations and others to discuss the bill and air concerns.
Democratic Senator Charles Schumer of New York, one of the bill's main authors, emerged from that meeting acknowledging the long road ahead after months of intensive negotiations over legislation that would make the 11 million undocumented residents wait 13 years before qualifying for citizenship.
"There are obviously going to be changes. But we've agreed, all of us, that we can't let the core of the bill be undone," the New York Democrat said.
Angela Kelley, an immigration expert with the liberal Center for American Progress, said the meeting was "largely very sunny."
But she and other immigration reform advocates rattled off several concerns with the bill that will be presented to the Senate Judiciary Committee.
While saying that they would push for changes, they also acknowledged that all sides must be careful not to do anything to stop the momentum for an immigration bill this year.
Reform efforts got a major boost after Hispanic-American voters soundly rejected Republican candidates in last year's elections. That growing bloc of voters lashed out after hearing Republican presidential candidate Mitt Romney talk about making life so hard for illegal immigrants that they "self deport."
Immigration groups' objections to the bipartisan bill ranged from excluding gay couples from new protections to worries about "triggers" that have to be in place - ensuring that U.S. borders have been secured against illegal entry - before any of the undocumented can begin receiving permanent residence and then U.S. citizenship.
Referring to the bill's pathway to citizenship, Frank Sharry, executive director of America's Voice, which pushes immigration reform, said: "Man, it's got a lot of rocks and boulders in it and it's long. Too long for us."
Sharry added a "sleeper issue" was emerging over a provision that would force newly legalized residents to renew their status after six years. "You're going to have to meet certain income and work requirements. What does that mean for domestic workers and day laborers and homemakers?" he asked.
Furthermore, there is mistrust in the immigration reform community over whether future, more conservative administrations will either slow or block citizenship for some of the 11 million, Sharry said.
For African-American members of Congress, objections could surface over the bill's elimination of "diversity visas" that were largely aimed at helping émigrés from Africa.
Conservatives have much different worries, ranging from granting "amnesty" to those who are living illegally in the United States, to limits on certain types of foreign laborers to the potential costs of the bill, which they argue will come from benefits going to immigrants once they obtain permanent legal status.
Rubio, a potential presidential contender in 2016, has taken on the role of rebutting conservative objections. He spent part of Wednesday trying to squelch a spreading line on conservative blogs and talk radio that the legislation includes free cellphones - dubbed "Marcophones" by the right - for some who work near the U.S. border with Mexico.
Rubio's office put out a statement explaining that the provision is designed to help enhance communications for border residents so they can report violence in the region.
Underscoring the difficulties of passing a bill, Schumer said some Republican senators from the South raised concerns with agricultural provisions late on Tuesday, sparking a last-minute round of closed-door negotiations before the bill was publicly posted.
Schumer said those senators' concerns were met and added that the legislation is starting from a much stronger position than a previous bill did in 2007 before it ended in failure.
Citing improvements in the 2013 bill versus 2007, Schumer said: "The path (to citizenship) was not just onerous, it was impractical. They did not have an agreement on guest workers with business and labor on board. We have agreement."
Despite those improvements, Rubio urged the public to "read this bill and tell us what we can do to make it better."
Meantime, a bipartisan group working in the House of Representatives said that it could soon set forth its own proposal.
House passage of a comprehensive bill is thought to be even more fraught with difficulties than in the Senate.
Many conservative House Republicans prefer that Congress bypass a comprehensive approach and take limited steps on immigration, such as strengthening border security and improving high-tech firms' access to skilled foreign labor.
But immigration groups vow to step up their push for a comprehensive bill, now that legislation has been unveiled.
"Now it's going to be the immigration reform movement against the nativists," Sharry said. "We're back in the public sphere and that, from our point of view, plays to our strengths. It's no longer in a back room with eight members. Now it's a public fight."
(Editing by Fred Barbash, Doina Chiacu and Tim Dobbyn)