(Agencies)
Updated: 2008-04-23 11:09

PITTSBURGH -- Barack Obama, who said Republican John McCain would be an improvement over President Bush, argued Tuesday that his comment didn't undercut Democrats' contention that the GOP nominee-in-waiting offers the same as the unpopular president.

"To say that John McCain and some of his instincts may be better than George Bush's, that's a low bar," the Democratic presidential candidate said, adding that he also has stressed that McCain is offering "warmed-over versions of Bush foreign policy and economic policy."

"So, there's no contradiction there," Obama said.

Democratic presidential hopeful Sen. Barack Obama, D-Ill., points to diners as he talks to the media at Pamela's Diner in Pittsburgh, Tuesday, April 22, 2008. [Agencies]

In Reading, Pa., on Sunday, the Illinois senator was trying to argue that he is the better choice over Democratic rival Hillary Rodham Clinton in Tuesday's primary in Pennsylvania. But Obama, who often claims that McCain would be an extension of Bush's tenure, ended up inadvertently complimenting McCain.

"You have a real choice in this election. Either Democrat would be better than John McCain. And all three of us would be better than George Bush," Obama said.

That comment contrasted with what the Democratic Party as a whole often says about McCain as it tries to make the general election a referendum on Bush -- that the likely Republican nominee offers a vision identical to that of the president on everything from Iraq to the economy.

It also gave Clinton an opening to criticize Obama: "We need a nominee who will take on John McCain, not cheer on John McCain."

Asked Tuesday about his comment on McCain, Obama tried to turn the tables on Clinton.

"I think Senator Clinton's suggesting that she and John McCain are the two people who are qualified to be commander in chief is probably something that could end up coming back to haunt us in November," Obama told reporters.

Last month, Clinton told retired military leaders that presidential candidates must "be able to demonstrate we can cross the commander-in-chief threshold ... I believe that I've done that. Certainly, Senator McCain has done that and you'll have to ask Senator Obama with respect to his candidacy."

Said Tucker Bounds, a McCain spokesman: "Barack Obama's inability to be strong and stand beside his own campaign rhetoric is revealing. If Barack Obama can't stand by his word now, how is he going to stand up for hardworking Americans and rebuild the economy?"