Seeking to end weeks of controversy, Texas Gov. George W. Bush apologized today for having spoken at Bob Jones University without "disassociating myself from [the] anti-Catholic sentiments and racial prejudice" of the fundamentalist college and its leaders.

In a letter to Cardinal John O'Connor of New York that also went to Catholic officials in other major states whose primaries loom immediately ahead, the Republican presidential hopeful said his silence on these controversial matters in his Feb. 2 appearance at the Greenville, S.C., school "was a missed opportunity, causing needless offense, which I deeply regret."

Bush's visit to Bob Jones was strongly criticized by his rival, Arizona Sen. John McCain, in phone calls targeted to Catholic voters in Michigan--calls that Bush said today had "slandered" him with the "suggestion that I tolerate anti-Catholic bigotry."

In a Seattle news conference, Bush accused McCain of hypocrisy in first denying any knowledge of the calls and then telling the New York Times that he had read and approved the script. "That's not plain talk; that's parsed talk," Bush said. "This is a man who said, 'I'm going to tell the truth and run a positive campaign.' If the facts are what they are, it sounds like he might have violated both."

McCain spokesman Dan Schnur said, "Now that Governor Bush has apologized . . . it's difficult to see what he finds so objectionable about the calls."

Rep. Jennifer Dunn, co-chairman of Bush's campaign here, said tonight her office had received reports of calls from McCain supporters similar to those that flooded Michigan.

Bush's appearance at Bob Jones on the opening day of his successful campaign in the South Carolina primary has boomeranged against him, as the McCain campaign, Democratic contenders Al Gore and Bill Bradley and numerous editorials have assailed his standing with school officials, who bar interracial dating by students and who have called the Roman Catholic church a "Satanic cult."

For weeks, Bush has defended his appearance by saying he quickly repudiated any such views for himself and by pointing out that many other officials in both parties had spoken on the same campus.

But with primaries in Virginia and Washington on Tuesday, a caucus in North Dakota that night, and contests a week later in New York, Massachusetts, California, Maryland and Ohio, all states with large Catholic populations, the political risk of leaving the issue on the table was obvious.

Bush did not dispute the political concerns that prompted his letter to the cardinal but said he was "offended" by any suggestion of bias on his part. He said he was "amazed" that anyone would suspect he harbored prejudice. "As a public official, I take seriously my duty to encourage tolerance and respect for the religious views of others. As a Christian, I see Catholics as my brothers and sisters in Christ."

Taking aim at McCain, he added that he would not tolerate "guilt by association." McCain was questioned closely on ABC's "This Week" about his initial denials that his campaign played any role in the anti-Bush telephone message in Michigan. The recorded message, described by the caller as a "Catholic voter alert," was paid for and approved by the McCain campaign. It said that because of Bush's silence about Bob Jones University's "anti-Catholic bigotry . . . many Michigan Catholics now support John McCain for president."

McCain said the calls were "factually true" but were mischaracterized when he was asked whether he had accused Bush of bigotry. "When they said, are you making calls that say Governor Bush is anti-Catholic, I said no because we're not and we didn't," he said.

McCain also cited tactics used against him in South Carolina, including an e-mail by a Bob Jones University professor that accused him of fathering several illegitimate children.

On another issue, Bush criticized McCain for bowing out of a scheduled March 2 television debate in Los Angeles, their only planned meeting before the winner-take-all battle for 162 delegates in the largest state. McCain said he scheduled himself in New York for that date after Bush had suggested he might pass up the debate. But Schnur said skipping the debate is "definitely a mistake. . . . It gives an inaccurate impression that we're not contesting the state."

On "Fox News Sunday," Bush's chief strategist, Karl Rove, accused McCain of making "sleazy, anonymous phones calls in the name of phony groups." Rove and former New Hampshire senator Warren B. Rudman, McCain's national co-chairman, also clashed on NBC's "Meet the Press," with each accusing the other campaign of engaging in smear tactics.

Over the weekend, Bush picked up 26 more delegates to the Republican National Convention by winning caucuses in Guam, American Samoa and the U.S. Virgin Islands and about 93 percent of the vote in today's Puerto Rico primary. The victories give Bush 93 delegates to McCain's 96; a total of 1,034 is needed to win the GOP nomination.

Staff writers Dan Balz in Los Angeles and Edward Walsh in Washington contributed to this report.