I think labor issues could unite the core of the party...
Democrats' stances on immigration and labor are contradictory to say the least.
Democrats aren’t willing to support immigrants explicitly as workers who deserve solidarity, because that would be class politics of the kind contemporary Democrats are uncomfortable with, so they would rather frame it as something DEI-adjacent or at best, a question of human rights. The human rights/social justice approach only gets them so far though.
If they want to take that tack, fine, it's just not pro-labor.
How so?
If I double the supply pool with people willing to work for less per hour or benefits than you, your bargaining power declines. Labor is on an upswing the past few years as far as getting pay raises, and the reason why is a shortage of labor out there, which shows up in the unemployment rate. It also cannot be underestimated how the under the table aspects of some immigrant labor effectively kills those that are citizens and have to follow the law otherwise the IRS pays them a visit. Do you know how much a competitive advantage a worker has that does not have a W-2, 1099's disappear, does not pay payroll, FICA, Social Security, state, and local taxes have over one that does? Meanwhile no one does anything to the business owners and individuals that hire these people.