Tea Party activists and some GOP delegates are vowing to drive Gov. Gary Herbert from office in 2012 unless he vetoes the immigration reform package approved by the Utah Legislature last week.
"It is outrageous that any lone state would attempt to pass radical amnesty legislation that has been rejected by Congress and a majority of Americans again and again," said William Gheen, head of Americans for Legal Immigration.
Hispanic groups want the governor to strike down the enforcement bill and have announced a two-week boycott of Utah businesses, beginning March 14.
Local and national groups on both sides of the immigration debate have threatened lawsuits to halt the reforms.
Breaking from the hard-line approach taken by Arizona, which passed a draconian enforcement law last year, the hybrid package recognizes the need to control illegal immigration and the demand for unskilled labor despite high unemployment nationally.
In framing the reforms, Utah lawmakers sought to protect the state economy and avoid separating families by deportation, while pushing a reluctant US Congress to deal with the problem of undocumented workers.