The vote was 55-40 against a proposal by Sen. Johnny Isakson, R-Ga, who said that anything less than a border security-first approach amounted to "a wink and a nod one more time to those who would come here" unlawfully.
Republican and Democratic supporters of the sweeping Senate bill said Isakson's approach would be self-defeating and derail the approach that Bush backed in Monday night's prime time speech from the Oval Office. "We have to have a comprehensive approach if we're going to gain control of the borders," said Sen. Edward M. Kennedy, D-Mass.
Eager to blunt any political fallout from opposing Isakson's proposal, the bill's sponsors countered with an alternative of their own. Backed by Sen. Ken Salazar, D-Colo., it said immigration changes envisioned in the legislation could proceed if the president declared they were in the national security interests of the United States.
The Senate cast its first votes on the immigration bill as Mr. Bush renewed his call for Congress to act. "The objective is, on the one hand, protect our borders; and, on the other hand, never lose sight of the thing that makes America unique which is, we're a land of immigrants and that we're not going to discriminate against people," he said at a news conference with Australian Prime Minister John Howard.
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Mr. Bush drew continued criticism from House Republicans for his speech, and the White House sought to emphasize the border security elements of the president's plan, CBS News senior White House correspondent Bill Plante reported.
"This is going to be a tremendous enforcement support partnership," U.S. Border Patrol Chief David Aguilar told reporters at the White House, anticipating the deployment of up to 6,000 National Guard troops to states along the Mexican border.
"We can certainly do what is asked by our commander in chief," added Lt. Gen. Steven Blum, National Guard Bureau Chief.
Blum, Aguilar and others stressed that National Guard forces would function in support roles, leaving front-line law enforcement against illegal immigrants in the hands of federal Border Patrol agents.
Republicans expressed support for new attempts to secure America's porous borders, but they rebelled against another element of what Bush calls a comprehensive plan to alter immigration laws. The president would like a path to citizenship for illegal immigrants who are already in the country, but many House Republicans call that amnesty for lawbreakers, reports CBS News chief White House correspondent Jim Axelrod.
"Thinly veiled attempts to promote amnesty cannot be tolerated," said Rep. Tom Price, R-Ga. "While America is a nation of immigrants, we are also a nation of laws, and rewarding those who break our laws not only dishonors the hard work of those who came here legally but does nothing to fix our current situation."
Any legislation that emerges from Congress will eventually come from House-Senate negotiations.
But first, the Senate had to act, and there, Mr. Bush's speech won praise from Republicans and Democrats alike lining up behind long-stalled legislation.
Sen. Mel Martinez, R-Fla., said he and other supporters had the support needed to defeat any crippling amendments offered by critics. Mr. Bush's speech "solidified some votes," he told reporters.
"The president gets it," added Sen. Dick Durbin, D-Ill.
Behind the rhetorical lovefest lay political calculations, politicians of both parties stressing their election-year credentials as tough on illegal immigration in an era of terrorism.
Still, the impact on the Senate floor was to demonstrate support for legislation that combined several elements, toughening border control, creating a new guest worker program and opening the door to eventual citizenship for most of the estimated 12 million illegal immigrants already in the country. The same bill includes provisions to toughen enforcement of laws against the hiring of illegal workers by businesses.