There will be a “major intraparty battle over immigration if Paul comes forward,” predicted Rep. Steve King (R-Iowa), a well-known immigration hard-liner, in an interview this week. “And a majority of the conference is on my side of this argument.”…

The politics of immigration ebbed and flowed during Ryan’s years on Capitol Hill, and Ryan has taken some hard-line positions, too. He voted in favor of an illegal immigration crackdown bill in 2005 from Rep. Jim Sensenbrenner, a fellow Wisconsin Republican — legislation that bolstered both interior enforcement policies and border security provisions but triggered a wave of demonstrations nationwide protesting the bill.

But that same year, Ryan endorsed legislation from Rep. Luis Gutierrez (D-Ill.), and then-Arizona GOP Reps. Jim Kolbe and Jeff Flake (now a senator) — a complete overhaul of the immigration system that would legalize undocumented immigrants, and was backed by Sens. Ted Kennedy (D-Mass.) and John McCain (R-Ariz.) in the Senate.

Ryan “was a co-sponsor of the bill that Gutierrez was in favor of,” said Mark Krikorian, executive director of the Center for Immigration Studies, which favors stricter migration policies. “For me, that tells you everything.”