Tensions emerged in the Capitol Wednesday as shouting protesters interrupted a hearing and Republicans trumpeted border security during the Senate's first hearing examining an overhaul of the immigration system.

At stake is national leaders' latest –and most serious– effort in years to possibly dramatically reverse the status of the country's estimated 11 million undocumented immigrants.

"The president is right: Now is the time," Senate Judiciary Committee Chairman Patrick Leahy, D-Vt., told a packed hearing room a day after President Barack Obama used his State of the Union address to renew his call for immigration reform.

The emotions surrounding the issue were on display as protesters shouted down the first witness, Homeland Security Secretary Janet Napolitano, calling for an end to deportations.

The protesters were ushered out. Napolitano declared the border more secure than ever and rejected the argument that border security must be the focus before comprehensive immigration reform or any pathway to legalization can be done.

"Too often the border security refrain simply serves as an excuse," Napolitano said. "Our borders have in fact never been stronger."

A top committee Republican, Sen. Jeff Sessions, R-Ala., quickly contradicted her and Leahy, saying the administration has not focused sufficiently on enforcement. "You mean amnesty only, you really mean we're not going to have enforcement, we've got to have amnesty first," he contended.

"What do you want to do with me?" an emotional Jose Antonio Vargas demanded of senators. "How do you define American?"

A former journalist who acknowledged his illegal status in a high-profile piece in The New York Times Magazine in June 2011, Vargas recalled his journey to the U.S. from the Philippines in 1993. He told lawmakers that he never knew he was here illegally until he applied for a drivers' permit, and that he lived for years in fear until he decided to go public and start an advocacy group. He has so far avoided deportation.

"Too often, we're treated as abstractions, faceless and nameless, mere subjects of debate rather than individuals with families, hopes, fears, and dreams," Vargas told committee members. "We dream of a path to citizenship so we can actively participate in our American democracy." 

The hearing came amid a concerted focus on immigration reform from the White House to Capitol Hill. Obama says he is determined to finally make good on his promise to the Latino community to sign into law a comprehensive immigration bill with border security, employer enforcement, improvements to legal immigration and a path to citizenship for undocumented people already living in the U.S. Meanwhile, a bipartisan group of eight senators has been meeting to develop a bill by next month that accomplishes eventual citizenship for undocumented immigrants while also containing enough border security and enforcement measures to gain conservative support.

Yet, as Wednesday's hearing made starkly clear, the success of any legislation is no sure thing with many Republicans still deeply skeptical.

Several Republicans on the panel rejected Napolitano's contention that the border is secure, questioned why earlier immigration laws never yielded the promised enforcement mechanisms, and branded as "amnesty" attempts to legalize undocumented immigrants.

"I do not believe the border is secure and I still believe we have a long, long way to go," said Sen. John Cornyn, R-Texas.

Based on reporting by The Associated Press.

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