Romney to Campaign with McCain in Ariz.

PHOENIX — Former Massachusetts Gov. Mitt Romney will campaign with John McCain in Arizona next week.

Romney and McCain were bitter rivals for the Republican nomination for president in 2008. But Romney aggressively campaigned for McCain in the general election and has endorsed the Arizona senator in his re-election bid.

McCain is facing a tough primary challenge from former U.S. Rep. J.D. Hayworth.

McCain and Romney will appear together June 4 at a town hall meeting in Mesa. Romney also campaigned for McCain in March while in Phoenix for a book signing.