PHOENIX - Sen. John McCain's complex relationship with President Bush can be summed up this way: Can't live with him, can't live without him.

The president's popularity is at rock bottom. Even allies privately fret that he is an albatross for the Republican looking to succeed him. Voters are crying out for change amid a prolonged Iraq war and a weak economy.

But Bush also is beloved among GOP loyalists. He is a proven campaigner who can raise serious money. Those are huge assets as McCain works to rally the Republican base and fill his coffers while facing the Democrats' enthusiasm and record-breaking fund-raising.

Bush and his would-be successor appeared together yesterday for the first time in nearly three months at an event that epitomized both elements of their tricky alliance: a fund-raiser with GOP faithful at a private home, without the media to document it.

By the McCain campaign's own planning, the only time Bush and McCain were captured on camera was after the event - too late for most evening newscasts - on the airport tarmac in the shadow of Air Force One, just before the president departed.

All smiles, Bush and McCain shook hands and then waved at reporters but kept a safe distance and spurned efforts to get them to talk. Bush then boarded the plane as the Arizona senator and his wife, Cindy, watched from the ground.

McCain's fund-raisers typically are closed to the media; the White House deferred to the campaign. Yesterday's fund-raiser at the home of prominent Republican Jack Londen and his wife, Lynn, raised an estimated $3 million for the Republican National Committee.

Illinois Sen. Barack Obama, the Democratic front-runner, got in a jab in advance.

"No cameras. No reporters. And we all know why," Obama chided while campaigning in Nevada. "Sen. McCain doesn't want to be seen, hat-in-hand, with the president whose failed policies he promises to continue for another four years."

For months, Democrats have portrayed McCain as an extension of Bush. They have argued that McCain offers the same policies, despite his willingness to break with the Republican Party on a range of issues. And they ran ads showing footage of Bush and McCain embracing each other in 2004, including one that said: "If all he offers is more of the same, is John McCain the right choice for America's future?"

The liberal group MoveOn.org also unveiled a commercial yesterday that links images of Bush and McCain over the theme song of

The

Patty Duke Show,

a 1960s sitcom about identical teenage cousins who "laugh alike, they walk alike, at times they even talk alike."

Bush and McCain last appeared together publicly in early March, the day after McCain sewed up the nomination.