But in asking the Republican firebrand not to leave the GOP, Bush has drawn criticism from key Republican and conservative leaders, as well as from some Jewish officials.
The Republican presidential front-runner last week urged Buchanan to stay in the party, telling the Associated Press last week that it was "important" if he wins the nomination "to unite the Republican Party. I'm going to need every vote I can get among Republicans to win the election."
A Reform Party bid by Buchanan could siphon off at least 4 percentage points from Bush, according to most polls.
Just days earlier, Bush had met with Jewish Republicans and the heads of several major Jewish organizations to discuss a range of Jewish concerns, including the Middle East peace process, church-state separation and gun violence.
At that private meeting in Austin, Texas, Bush, according to officials in attendance, said he disagreed fundamentally with Buchanan's views. But he indicated that he did not want to draw more attention to Buchanan by engaging him in a debate about his assertions in his book, "A Republic, Not an Empire," that Nazi Germany posed no threat to the United States after 1940 and that Americans were deceived concerning the need to enter the war.
Instead, Bush decided to appeal for party unity by urging Buchanan not to bolt the GOP at a time when Buchanan appears likely to seek the Reform Party nomination for the presidency.
Bush's stance places him at odds with GOP rival Sen. John McCain, who said Buchanan should be kicked out of the party because of his fringe views. McCain, echoing a sentiment expressed by some in the Jewish community, said Bush was putting politics ahead of principle.
Responding to criticism, Mindy Tucker, a spokeswoman for the Bush campaign, said: "Gov. Bush is a leader who believes in uniting our party much like Ronald Reagan did, instead of driving wedges between people. The Republican Party is a contest, a contest of ideas, and Republican voters will have a chance to express their opinion on this issue in the primary."
She declined to elaborate on Bush's political considerations, but she said of Buchanan's views: "Gov. Bush disagrees emphatically with the strange ideas expressed by Pat Buchanan about World War II. He believes that World War II was a great and noble cause."
It remains to be seen what, if any, impact Bush's reaction to Buchanan will have on his campaign's outreach efforts to Jewish voters.
By most accounts, Bush -- a pro-life governor who has said he wants church and state to "work together," has endorsed displaying the Ten Commandments in schools and once said that only followers of Jesus can go to heaven -- already has a difficult road ahead in courting Jews, who have historically backed Democratic candidates.
Jewish leaders, for their part, signaled disapproval of Bush's handling of the matter, but avoided sharp criticism of Bush.
Abraham Foxman, national director of the Anti-Defamation League, said that while he was disappointed with Bush's response, he was far more troubled by the attitude toward Buchanan in political circles and what he called a lack of recognition of the "nature and of the poison of this man."
"I am troubled that there is a man who is an anti-Semite, who is a Hitler apologist, a Nazi war criminal defender, an Israel-basher, a racist on so many levels, and good, serious people are still trying to waltz around him gingerly," said Foxman, who attended the meeting with Bush in Austin last week.
If people were to recognize "who he is and what he is," he said, "there would be no hesitancy to say that this man does not belong in the political mainstream of our country."
Richard Heideman, president of B'nai B'rith International, said: "I would like to see him [Bush] reject Buchanan, and I reject Buchanan. But in the context of the meeting we had Wednesday, I understand the outreach he has expressed [toward Buchanan] at the present time."
Jewish Democrats, meanwhile, were quick to pounce on the GOP front-runner.
"Bush made a terrible choice," said Ira Forman, executive director of the National Jewish Democratic Council. "He made a political calculation, and he said it doesn't matter what this guy stands for -- if he's obsessed with Jews, if he's an anti-Semite, if he's a xenophobe. What matters is what can save one extra vote for George Bush. And that's terribly disappointing."
The Republican Jewish Coalition last week said Buchanan's views were abhorrent and that he had no place in the Republican Party. But Matt Brooks, the group's executive director, defended Bush's stance, saying it made practical sense.
"Buchanan is leaving the party regardless of what George W. Bush or anybody else has to say," Brooks said. "What he's done is to make sure Buchanan can't leave the party and take Republican support with him, saying he was forced out of the party."