Former U.S. Attorney Chris Christie is currently running ahead in the polls as the Republican nominee for Governor of New Jersey, but the Democrats are now aiming to trip him up using an ages-old maneuver: Attacking Christie for presenting himself as a moderate now, compared to the more right-wing stuff he said when he was campaigning for the Republican nomination.

The campaign of Democratic Gov. Jon Corzine has put up this Web video, going after Christie for saying he agreed on renewable-energy issues with President Obama -- who is very popular in this Democratic state. However, we see that Christie took a different stance on the environment when he was competing with a much more conservative rival within the GOP:

Christie said at a forum: "I've got a feeling that you will see in January 2010, a lot of battles between the Christie administration DEP and the Obama administration EPA."

Of course, candidates on both sides of the aisle frequently take more hard-line stances during primaries, then tack to the middle for the general elections. The key here is that New Jersey Democrats often win elections by tying their Republican opponents to the conservatism of the national GOP. And the Corzine campaign is now beginning to play that angle.

The Christie campaign has not returned a request for comment at this time.