Top Senate Democrats launched on Wednesday another bid to pass a comprehensive immigration reform they say will enhance U.S. economic productivity and national security even as it provides a path to legalization for 11 million undocumented immigrants.

Sens. Bob Menendez of New Jersey, Dick Durbin of Illinois and Patrick Leahy of Vermont held a Capitol Hill press conference to present a measure similar to one that was defeated in 2007.

Menendez, the bill's author, said he was confident the measure would attract support from Republicans and called the legislation a "vehicle" that will propel the immigration debate in Congress.

Declining to put forward a timetable for hearings and debate on the bill, Leahy criticized current immigration law as harsh, while Durbin said the Menendez plan would make the United States more secure, more productive and more just.

The senators stressed the urgency of bringing the undocumented out of the shadows, given the importance of immigrant labor for U.S. economic sectors such as agriculture and hospitality.

The new bill includes elements to bolster border security - as demanded by Republicans - and to discourage firms from hiring undocumented workers, while establishing strict criteria for the legalization of immigrants who entered the United States without authorization.

To be eligible, an immigrant must have arrived in the country prior to June 1, 2011, have no criminal record, register with the government and pay a fine, be current with tax payments and learn English.

Menendez suggested that undocumented migrants who fail to register with authorities or who don't meet the eligibility criteria would face deportation.

The legislation also includes Durbin's DREAM Act, which offers permanent residence to undocumented high school graduates who enlist in the U.S. Armed Forces or attend college.

In another nod to Republicans, the bill likewise calls for all employers to be required to use the federal E-Verify program to determine whether applicants are authorized to work in the United States.

The 2007 immigration reform failed despite Democrats' control of both houses of Congress and the support of the then-Republican president, George W. Bush. Today, the GOP majority in the House of Representatives appears to be interested only in stricter enforcement of existing immigration laws.

The White House praised the Democratic senators' initiative and emphasized President Barack Obama's consistent support for comprehensive immigration reform.

Obama "has spoken clearly about the need to fix the broken immigration system in a way that responds to the economic and security needs of the United States in the 21st century," the White House Director of Hispanic Media, Luis Miranda, told Efe Wednesday.