Pro-immigration forces are planning rallies in such major cities as Washington, Los Angeles, Chicago, Miami, Houston and Denver to mark the Supreme Court formally hearing arguments in President Obama's immigration executive action case.

In all, some 20 demonstrations are planned across the country on Monday, April 18, all aimed at expressing support for the Obama administration's executive actions, which could save as many as four million undocumented immigrants from deportation.

As part of the D.C. demonstration, Grammy-award winning band La Santa Cecilia is scheduled to hold a live concert in front of the court building. Organizers have stated labor unions, undocumented workers and families and Facebook founder Mark Zuckerberg are also slated to be on hand.

Oral Arguments set to Commence on April 18

Oral arguments on the long festering issue are slated to begin on Monday, with the legality of the program known as DAPA sitting at the forefront of all the intense litigation.

"It hits close to home," said Jose "Pepe" Carlos, a DREAMer and band member. "I was undocumented for 25 years, it's really unjust and unfair that we're not given the credit we deserve as Latino Americano immigrants."

Carlos said he is no longer undocumented, but indicates his parents still are and he worries if DAPA is struck down by the Supreme Court, their right to remain in the U.S. could be thrown into jeopardy.

"Hopefully it goes through because it's not just my parents but a whole generation of parents who are going to benefit," he said.

Republicans take Hardline Stance on Immigration

Indeed, the stakes are high and the political battle lines have been drawn. The Republican led House of Representatives recently filed a brief with the court and will be granted time to address the justices during the oral arguments phase of the proceedings, where they will express their stern opposition to the president's actions.

Beyond that, Republican presidential front-runners Donald Trump and Ted Cruz have both expressed plans to carry out mass deportations if either of them is elected as Obama's successor. Trump has also vowed that he will build a massive wall along the Mexican border that will further keep out immigrants.

A recent Pew Research study found that more than 27 million Latinos will be eligible to vote this election season and a recent Washington Post-Univision national poll found that four in every five Hispanic voters now has a negative image of Trump and if the election was held today he would lose the Latino vote to Democratic front-runner Hillary Clinton by a 73 percent to 16 percent margin.

"We want to send a message that this is very personal for our community," said Rocio Saenz, SEIU International executive vice president. "We are in the moment where we are going to have to make a decision on what type of country we'll have."

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