NEW YORK (CNN) -- Former White House Press Secretary Scott McClellan, whose tell-all book blasts the Bush administration on issues including Hurricane Katrina, the election and the Iraq war, didn't say Friday whether he still considers himself a Republican.

Former Press Secretary Scott McClellan is defending his book on the White House.

But he did say he supports parts of Democratic presidential candidate Sen. Barack Obama's agenda.

"Some of what Obama says, his overall message, is very similar to the one we ran on in 2000 about changing the way Washington works and what I had so much hope in," said McClellan, who became the White House press secretary in 2003 after serving as spokesman for President Bush when he was the governor of Texas.

"But it's a very difficult thing to do, and I hope some of the Obama staff will take a look at [McClellan's book] and consider what they need to do if they become president."

McClellan also said he has "a lot of respect" for presumptive Republican presidential nominee Sen. John McCain.

In his 341-page book, "What Happened," McClellan writes that Bush and his advisers favored a "propaganda campaign" to the truth in the days leading up to the Iraq invasion. Read excerpts from the book »

McClellan also claims that key Bush aides intentionally misled him on major stories and that the administration's botched handling of the Hurricane Katrina aftermath was the defining moment of Bush's second term.

In an interview with CNN's Anderson Cooper, McClellan -- who has faced withering criticism from the White House and other Bush allies since his book was released -- declined to answer directly when asked if he still considers himself a Republican.

"Well, you know, there are things I like about the Republicans, Republican ideas, and there are Democrat ideas I like," he said.

"I've not made a decision in terms of the presidential election," he added. "I'm someone who believes in centrist governing philosophy. And that's what the president believed in as governor, but as president he moved too far to the right too often."

Earlier Friday, McClellan said he would be willing to comply with a possible congressional subpoena to discuss the administration's handling of prewar intelligence, telling CNN's Wolf Blitzer he'd be "glad" to share his views if asked to testify.

Rep. Robert Wexler, D-Florida, said Friday that McClellan, who left the White House in 2006, would be able to provide valuable insight into a number of issues under investigation by the House Judiciary Committee.

The committee is looking into the use of prewar intelligence, whether politics was behind the firing of eight U.S. attorneys in 2006 and the leaking of CIA operative Valerie Plame's identity, Wexler, a senior member of the Judiciary Committee, said.

In the book, McClellan says President Bush told him he had authorized the leaking of Plame's identity to the press. Watch Wexler call for McClellan to testify »

Facing a firestorm over his book, McClellan also confirmed reports Friday that he apologized to Richard Clarke for questioning his honesty after the former counterterrorism official published his own book critical of the White House.

"I don't expect we'll have a conversation [with Bush] any time soon," he said. "I don't need to ask forgiveness from him. My comments are sincere and honest and absolutely the truth from my perspective."

Speaking with Cooper, McClellan responded to one of the harshest criticisms he faced this week, from former senator and Republican presidential candidate Bob Dole.

Dole reportedly sent McClellan an e-mail saying every presidential administration has "miserable creatures like you ... who don't have the guts to speak up or quit if there are disagreements with the boss or colleagues."

The message accuses McClellan of reveling in the attention he received at the White House then cashing in with his book.

"I have great respect for Sen. Dole -- he's a great public servant and someone who has served in the military as well and someone who actually did try to work across the aisle with Democratic leaders at times, back before things got so bitterly partisan in Washington, D.C.," McClellan said.

"But I would encourage him to see what I say in the book before he makes those comments."

McClellan told CNN that reports the publisher of his book doesn't pay higher than six-figure advances to its authors is "an accurate account of things" but wouldn't say exactly how much of an advance he was paid.

"When people say, 'He's out there to make a profit,' one, they don't know me or my upbringing and my reasoning. They haven't had a chance to read the book," he said. "Two, they don't know ["What Happened" publisher] Public Affairs and the kind of publisher that they are."

CNN's Ed Hornick, Rebecca Sinderbrand and Alexander Mooney contributed to this report.

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