Barack Obama (web|news|bio) is fond of using a four-letter word to describe John McCain (web|news|bio) : Bush. Weary and wary of being linked so closely with the president, McCain says Obama is spreading a falsehood voters won't buy when he says McCain as president would deliver a third Bush term. Oh, to be the president of the United States these days.

Time was, it wasn't so awful to be associated with the leader of the country.

But the political reality is that Bush's approval ratings are near record lows, which makes him an easy target. Or at least not a guy being sought out for bear hugs.

The White House likes to point out that Bush is not on the ticket. Yet he remains in the thick of it.

Consider McCain's speech as Obama clinched the Democratic nomination Tuesday night.

Predictably, he spoke about his differences with Obama. Pre-emptively, he outlined a history of differences with Bush to undermine Obama's line of attack.

"You will hear from my opponent's campaign in every speech, every interview, every press release that I'm running for President Bush (web|news|bio) 's third term," McCain said. "You will hear every policy of the president described as the Bush-McCain policy. Why does Senator Obama believe it's so important to repeat that idea over and over again? Because he knows it's very difficult to get Americans to believe something they know is false."

In other words, America, I'm not Bush.

Yes, McCain said, he shares views with the president, particularly on national security. But he proudly listed a pattern of splitting with the president on energy and climate change, on spiraling spending and budget gimmicks, and on the administration's "mismanagement" of the war in Iraq (web|news) .

It so happens that this distancing came exactly one week after Bush was with McCain, in McCain's home state of Arizona, raising money for him at a big-dollar fundraiser. Bush raised an estimated $3 million in private that night. His public appearance with McCain was so short it was measured in seconds.

Obama had Bush on his mind too on the historic night he clinched the Democratic Party's nomination.

The Illinois senator lumped McCain with Bush on the economy and on current war policy in Iraq. And he called McCain's claims of independence dubious.

"There are many words to describe John McCain's attempt to pass off his embrace of George Bush (web|news|bio) 's policies as bipartisan and new," Obama said. "But 'change' is not one of them."

Bush administration officials expect such rhetoric from the Democrat in the race. Yet even when it comes from the Republican, the White House line is: No offense taken.

"Look, Senator McCain is different than President Bush. That's a fact. We understand that his campaign will reflect his policies and his vision for the future of the country," White House spokesman Scott Stanzel said. "I think it's worth remembering that President Bush's father didn't exactly emulate President Reagan. Vice President Gore did not copy President Clinton. Even Hillary Clinton demonstrated differences from President Clinton - and she's married to him."