The truth is that there is no line for most undocumented immigrants and the "regular channels" do not include them. Approximately 500,000 undocumented immigrants enter the U.S. each year – most coming to work and typically to do so in the service sector – yet there are only 5,000 green cards for unskilled workers. Until there are more legal avenues for employers to hire immigrant workers, undocumented immigrants will fill the gap and we will not gain the control over immigration that the American people demand.
The U.S. Chamber of Commerce called in 2013 for Congress to "create workable temporary worker programs that allow employers to hire immigrants for jobs in the U.S. in accordance with the demands of the economy," emphasizing that such programs "will promote job and economic growth – along with reducing the pressure of illegal migration."
Moreover, our current family visa system is woefully out of date. Countless immigrants who have already been approved for visas to join their U.S. families are forced to wait years (often more than ten) in order to come to the U.S. because of the current quota system and tremendous backlogs.