(CNN) - They were once bitter rivals. But that's so 2007 and early 2008, when John McCain and Mitt Romney were battling for the Republican presidential nomination.
Friday they team up in Arizona, as the former Massachusetts governor helps campaign for Sen. McCain, who's battling for a fifth term in office.
Romney, who may make another bid for the White House, is scheduled to be a special guest at a McCain town hall meeting in Mesa, according to the senator's campaign. McCain is facing a tough primary challenge from the right launched by former seven-term Rep. JD Hayworth, who most recently was a popular conservative radio talk show host. The two will face off in Arizona's August 24 primary.
After dropping out of the hunt for the presidency in early 2008, Romney quickly backed McCain and campaigned for the GOP nominee in the general election. He has endorsed McCain's Senate re-election bid and campaigned for the senator in Arizona in March, when Romney was in Phoenix for a book signing.
Follow Paul Steinhauser on Twitter: @psteinhausercnn
These guys are all hypocrites. How could you support someone for re-election when you thought the very same person you are supporting now was unfit to be a leader during the campaign back then?
Romney either had to make up (make up is a little nice word. What I meant was lying.) things to make McCain look bad or not giving him credit he deserved during the campaign.
Funny how you don't hear much from McCain when the Gov. of Arizona want's Mexicans to carry around papers to make sure they are legal! These are the same people who voted for McCain and now he's got nothing to say... ah election season!! He was a "maverick" but wait he's not now!!!
MCain wasn't born here, and Romney is from out of state. Somebody better check their papers while they are in Mesa!
Now they can flip flop together. Oh Magoo, you've done it again.
McCain and Romney are TWO OF A KIND . . . THEY DESERVE EACH OTHER!
McCain is getting more desperate every day.
I don't understand how one has-been campaigning for another has-been is seen as helpful. Both these guys had their chance and they were beaten (by a clearly better man) in the election that matters. Hanging around and pretending to be important (Wasilla's village idiot anyone?) is just plain stupid and a waste of time.
I wish everyone who lost in the last presidential election would retire and not act like they still matter.
Both these idiots need to retire and enjoy their vast fortunes.