Senate Democrats on Thursday sought to thread the political needle on immigration reform, offering a plan that mixes tough border controls with a pathway to citizenship for 12 million illegal immigrants. Majority Leader Harry Reid (D-Nev.) said he wouldnt set a deadline for obtaining GOP buy-in for the plan, but the initial Republican reaction was decidedly negative.Reid described the measure as an invitation to Republicans as he called for a new round of bipartisan talks. I say to our Republican colleagues, work with us to fix this broken system ... dont just say no. Reid refused to set a deadline for bipartisan efforts to produce a deal.I dont think it would be wise for us to set an arbitrary deadline, Reid said, adding that we are patient ... we need 60 votes to bring a bill to the floor.But the early prognosis for a bipartisan outcome was not good.In a joint statement, Sen. Lindsey Graham (S.C.) and Minority Whip Jon Kyl (Ariz.) two of the leading GOP voices on immigration reform rejected the framework and accused Reid and others of playing politics.A conceptual paper that promises everything to everyone is not the same as responsible legislation that compiles the best ideas from both sides of the aisle. The Senate Democrats proposal is nothing more than an attempt to score political points. It poisons the well for those of us who are working toward a more secure border and responsible, bipartisan reform of our immigration laws, the Republican duo said.Sen. Orrin Hatch (R-Utah) argued that instead of fixing our broken borders, Washington politicos are playing a cynical game of introducing so-called immigration reform that I fear will turn into nothing more than amnesty.But Democratic Senatorial Campaign Committee Chairman Bob Menendez (N.J.) placed the measure in the context of Arizonas controversial new immigration law and said this was no time to delay comprehensive immigration reform.Latinos and others do not believe they are second-class citizens. ... We understand the history, not only of this country but of the history of the world, that when one group of people become a suspect class, when one group of people are blamed for all the problems of a nation, history has taught us that has a sad ending. We will not let that happen, Menendez said, adding that Latinos will not wait for the counsel of patience.Democratic aides have said that while Reid would prefer Republican buy-in, the Majority Leader would look to pursue the bill even if those efforts fail.The 22-page legislative summary, based on the now-defunct talks between Graham and Democratic Conference Vice Chairman Charles Schumer (N.Y.), would establish a series of border security benchmarks that must be met before broader reforms are enacted.The bill also requires employers to ensure their workers are legal immigrants, includes new visa provisions for high-tech and low-skilled workers, and establishes a pathway to citizenship for the estimated 12 million undocumented people in the U.S.