Green Bay - New Jersey Gov. Chris Christie is expected in Wisconsin to campaign for fellow Republican Gov. Scott Walker.

Christie will first be visiting Green Bay for a luncheon with Walker and supporters Tuesday.

He's then going to the landscaping company, KEI Enterprises, in a Milwaukee suburb. Walker is facing a recall election that has become a national showdown over union rights.

Walker's decision to eliminate most collective-bargaining rights for public employee unions ignited a political war that has left Wisconsin as polarized as any state in the country.

The primary is May 8 and the general recall election is June 5.

In New Jersey, Christie has picked a protracted fight with the public teachers union and has forced pension and health care concessions from union workers through legislation.