This all stemmed from a point of view Newt communicated at the CNN debate relative to immigration policy. Newt argued that an illegal alien, who has been in the US for 25 years, should not be ripped away from his / her family and deported. Romney obviously saw this as an opportunity to appeal to the conservative base on the immigration issue.
Via the New York Times:
DES MOINES — An intense debate over immigration flared among the Republican presidential candidates on Wednesday as Mitt Romney declared that Newt Gingrich “offered a new doorway to amnesty” when he called for a “humane” immigration policy to avoid deportation for people who are deeply rooted in their churches and communities.However, as Newt pointed out via twitter, Romney communicated a position not long ago (2007) that places him to the left of the view expressed by former Speaker at the debate. This couldn't have been better if Gingrich had done this intentionally.
Mr. Romney, who is eager to stop the rise of Mr. Gingrich with the Iowa caucuses only six weeks away, signaled that he intended to go after his rival with the same vigor he used against Gov. Rick Perry of Texas two months ago when he said Republicans were “heartless” for standing in the way of offering education to children of illegal immigrants.
With the controversy likely to shape the next phase of the nominating fight, Mr. Romney repeatedly used the word “amnesty” during a campaign visit here to describe the position Mr. Gingrich outlined at a debate Tuesday night. While aides to Mr. Gingrich forcefully refuted the characterization of his plan as “amnesty,” a swift backlash erupted among conservative activists that could present the biggest test of his resurgent candidacy.
This is a flip-flop that would make John Kerry blush:
For the record, here is what Gingrich said that Romney decided to seize upon while ignoring his own words:
h/t Weasel Zippers