While conservative lawmakers remain split on comprehensive immigration reform, several conservative leaders from influential organizations are lining up behind the bill that would lead to the biggest immigration overhaul in decades.

The American Conservative Union, or ACU, and its allies are calling on conservatives to be the leaders on the issue. The ACU annually hosts the Conservative Political Action Conference in Washington, D.C., which brings together thousands of conservative lawmakers, thinkers and advocates.

Its allies include leaders of religious groups like Faithful Catholic Citizens, Latino advocacy organizations like Latino Partnership and right-leaning think tanks like the American Enterprise Institute.

This support comes as the Senate Judiciary Committee begins markup on the bill Thursday.

“We believe conservatives should be leading the way on this issue by supporting legislation that upholds conservative principles,” the ACU said in a statement. “Conservatives are ready to support immigration reform, so long as it is pro-economic growth, strengthens families, fosters assimilation and prevents another wave of illegal immigration from happening again.”

An estimated 11 million undocumented immigrants are living in America. The bill drafted by the Senate’s bipartisan Gang of Eight would provide a pathway to citizenship for those who qualify but would require they pay back taxes and other assessed fees. It will also improve border security and make E-Verify to check workers' immigration status for employers mandatory.

Critics like Sen. Jeff Sessions, R-Ala., fear wages for American workers will be reduced as a result of legalizing the undocumented immigrants. He started criticizing the bill even before it was unveiled.

However, the ACU called the bill “an important starting point” toward fixing what it and others believe is a broken system.

“This legislation is not perfect,” the ACU’s statement read. “We do not expect the bill without amendments to pass, and we encourage good-faith amendments to improve the legislation. ... America needs immigration reform.”