WASHINGTON — While preparing to give a major critique of the war in Iraq last month, Senator Clinton read a draft of the speech and added a few lines of her own.

“I would also consider, as I have said before, leaving some forces in the Kurdish area to protect the fragile but real democracy and relative peace and security that has developed there,” Mrs. Clinton said in the final version of the speech.

It was a small but important caveat in an otherwise harsh speech about ending the war — overshadowed by repeated promises to withdraw troops as quickly and responsibly as possible.

Advisers close to Mrs. Clinton, a Democrat of New York who confirmed that she personally inserted the lines, said it illustrated her approach to running for president these days — as a deliberate practitioner of foreign policy, with an eye toward the general election and the realities of governing if she becomes president.

That has been the subtext of her fights with Senator Obama, a Democrat of Illinois, in the past few weeks. Mrs. Clinton called his willingness to meet with leaders of hostile states “irresponsible and naive” after the Democratic debate in South Carolina two weeks ago, then responded coolly to his statement last week that he would not use nuclear weapons against terrorist cells in Pakistan.

Refusing to say whether she agreed with him on the specific question, Mrs. Clinton said she did not “believe any president should make blanket statements with regard to use or nonuse.” Although many experts said Mr. Obama was fundamentally correct that the American government would not use nuclear force in the region, Mrs. Clinton’s answer seemed more attuned to a general election campaign and a future presidency. Much has been made of Mrs. Clinton’s slow rhetorical shift from authorizing the war in 2002 to attacking it now. Less scrutinized have been her maneuvers along the way to try to avoid the trap that befell Senator Kerry, a Democrat of Massachusetts, in 2004 — being “for the war before he was against it,” as his Republican rivals mocked.

From her position on the Senate Armed Services Committee, Mrs. Clinton has developed something of a “third way” of talking about the war, by emphasizing the future and what she would do as president. Some of her advisers refer to her as “anti-war and pro-defense,” a stance skewered by advisers to Mr. Obama, who has said he is the only viable Democrat who opposed the war from the beginning.

Since her trip to Iraq shortly before announcing her candidacy, Mrs. Clinton has focused on the future in that country, and over time, questions about her original vote for the war appear to have faded somewhat. Although she was mildly booed at the Yearly Kos convention in Chicago over the weekend, rival Democratic strategists said they have been frustrated by their inability to capitalize more on Mrs. Clinton’s war vote.

But not everyone is sympathetic to her balancing act. “I think she’s reading the polls and running for president,” said Stephen Walt, a professor of international relations at Harvard’s Kennedy School of Government. “She followed the country into the war, and now she’s sort of following the country out of the war but doesn’t want to do it in any sort of way that opens her up to any line of criticism.”

Mr. Walt, who is not aligned with any candidate, added that Mrs. Clinton “has not been willing to take many positions that moved her outside what the comfortable Washington consensus was at that moment.”

The Obama campaign declined to directly criticize Mrs. Clinton on her foreign-policy positions.

“All I can say is that Senator Obama has been a strong and consistent opponent of this war from the start because he believed it would mire us in an endless civil war and strengthen Al Qaeda,” said David Axelrod, a senior adviser to Mr. Obama. “That judgment and willingness to challenge the conventional thinking of Washington is an important quality in the next president.”

Nonetheless, in an election year in which Iraq may well be the defining issue, Mrs. Clinton remains the clear front-runner nationally. She is running even with Mr. Obama and a former senator of North Carolina, John Edwards, in Iowa, arguably the most anti-war early-voting state.

Mrs. Clinton advisers say they see her rising on parallel tracks: among liberals who believe her when she says she would end the war, and among centrists who believe she is “tough enough” to defend the country. A recent Washington Post-ABC News poll showed Mrs. Clinton ahead among Iowa voters on four key attributes: her ability to handle the situation in Iraq, strength as a leader, experience to be president and having the best chance to win in November.