Being an asshole is a necessary, but not sufficient trait for any Republican presidential hopeful. To wit, in 2008 Tom Tancredo was as big an ass towards immigrants as imaginable without requiring a permanent application of Charmin, yet it wasn’t enough to win. John McCain was sufficiently a prick to navigate a crowded field and win the nomination.

Unfortunately for Haley Barbour, he’s about to learn that he wasn’t sufficiently an ass in private life to please the rabid right. While discussing his work as a lobbyist on Fox News yesterday, Barbour left out the fact that he lobbied for the Mexican government to create a legislative pathway to citizenship for undocumented immigrants. Michael Scherer runs someone’s opposition research here:

Barbour may be eager to showcase his record, but one of Barbour’s foreign lobbying clients could cause him some troubles in the 2012 Republican primary, if he decides to run. According to a State Department filing by Barbour’s former lobbying firm, The Embassy of Mexico decided to retain Barbour’s services on August 15, 2001, to work on, among other things, legislation that would provide a path to citizenship for foreigners living illegally in the United States—what opponents of immigration reform call “amnesty.” “Haley Barbour and I will lead the BG&R team,” wrote Lanny Griffith, Barbour’s former business partner, in the filing. According to subsequent filings, Barbour’s work included “building support in the legislative branch for passage of a bill related to Section 245(i) of the Immigration and Nationality Act.” As part of that work, Barbour’s firm arranged meetings and briefings with “Senators, members of Congress and their staffs, as well as Executive Branch Officials in the White House, National Security Council, State Department, and Immigration & Naturalization Service.” Barbour’s firm charged Mexico $35,000 a month, plus expenses.

I don’t know who’s pushing their research on Barbour to Scherer, but the goal is clear: show that Haley Barbour is too soft on immigration for the Republican base. Clearly Haley Barbour is not enough of an ass to be a serious Republican presidential candidate, at least when it comes to immigration.