President Barack Obama heads to Las Vegas on Friday to rally public support for his executive order that will overhaul the country's immigration system.
Obama will hold a campaign-style event aimed at convincing Americans of the merits of the plan, which lifts the threat of deportation for millions of undocumented residents.
The president laid out his plan in a speech from the White House late Thursday, bypassing Congress and enraging Republicans who say they will try to stop him.
"If you've been in America for more than five years; if you have children who are American citizens or legal residents; if you register, pass a criminal background check and you're willing to pay your fair share of taxes, you'll be able to apply to stay in this country temporarily, without fear of deportation," Obama said.
"You can come out of the shadows and get right with the law."
The new executive order, which will take effect in roughly six months, offers temporary work permits to around 4.7 million qualifying undocumented immigrants.
Republicans slam action
Republicans denounced the president's action as amnesty, saying it will encourage new waves of illegal immigration. Many vowed an all-out fight to repeal the plan.
House Speaker John Boehner was among those who say the order is unconstitutional.
Boehner said the move to circumvent Congress could jeopardize legislative efforts.
"All year long I have warned the president that by ... threatening action repeatedly on immigration, he was making it impossible to build the trust necesary to work together," Reuters reported Boehner as telling reporters. "With this action, the president has chosen to deliberately sabotage any chance of ... bipartisan reform that he claims to seek."
In an earlier video statement, Boehner accused the president of acting like a "king" and an "emperor."
Obama defended the move's legality, saying both Democratic and Republican presidents have for decades passed similar orders. He blamed gridlock in Congress for making such action necessary.
"To those members of Congress who question my authority to make our immigration system work better, or question the wisdom of me acting where Congress has failed, I have one answer: Pass a bill. I want to work with both parties to pass a more permanent legislative solution," Obama said.
Immigration reform bill on hold
The Democratic-controlled Senate passed an immigration reform bill more than a year ago that was supported by both parties. But leaders in the Republican-controlled House have refused to bring it up for a vote.
It became even more unlikely that Congress would pass an immigration reform bill after this month's midterm elections, which saw Republicans gain a majority in both houses beginning in January.
It is not clear how Republicans will choose to fight Obama's order. Some have threatened to shut down the government, while others are looking for ways to ban funding just for the plan itself.
Many have said they will challenge the order in court. But numerous legal experts have said that the president's moves have legal precedent.
The president is expected to sign the immigration order at a Las Vegas high school on Friday afternoon.
Some information for this report was provided by Reuters.