George Allen (R) came out swinging today in the first debate of Virginia's U.S. Senate race, peppering two-term incumbent Charles S. Robb (D) on issues ranging from crime and taxes to Robb's strong support for Clinton administration initiatives.

What was billed as a joint appearance at a Virginia Press Association conference to discuss political news coverage turned immediately into a civil but spirited preview of a titanic November election featuring two former governors, each a landmark figure in the modern life of his state party.

Allen was on the offensive for nearly 90 minutes, attacking the rates at which paroles were granted when Robb held the reins of state government in the early 1980s and linking him to Clinton, whose "sordid and tawdry" side was revealed to the country by the Monica S. Lewinsky scandal, Allen said.

Robb, mild-mannered throughout, gently chided Allen at one point about verifying the accuracy of his statistics on violent crime, saying "we'll come back and talk about it" when all the facts are on the table.

"Well, we can do it right here," Allen shot back, "since we're here."

At another point, Allen asserted that Robb voted with President Clinton 90 percent of the time, and Robb interrupted him to say the real number was 85 percent. Allen promptly replied: "Oh, 85 percent!"

"I don't think that anybody in Virginia agrees with President Clinton's policies on taxes, on welfare, on campaign finance--on any of his ideas 85 percent of time," Allen said.

On taxes, Allen attacked Robb for his support of a major federal tax increase during his first term and a proposed 50-cent-a-gallon gasoline tax, but Robb said his vote for the 1993 deficit reduction bill helped lay the groundwork for the largest peacetime economic expansion in U.S. history.

Both candidates appeared relaxed, calling one another "Chuck" and "George," jointly regretting their constant pursuit of campaign contributions and even agreeing on some ideas, such as a taxpayer checkoff to fund a program to help secure health care for the nation's uninsured.

Meanwhile, their aides treated the joint appearance as gravely as any first debate of a brutal contest that will probably cost at least $20 million. Robb, 60, had his chief of staff, campaign manager and press secretary in tow; Allen, 47, had several campaign operatives along as well.

Afterward, spokesmen for each side played spin doctor with reporters. The Allen camp distributed four fact sheets, including one evidently printed while the two candidates were still talking, documenting the Robb record; Robb aides handed out seven pages of data designed to show that Virginia kept a lid on crime during his years in the Executive Mansion, especially when contrasted to national rates at the time.

"We were ready," said Ray Allen, a Richmond-based GOP strategist who is not related to his longtime client, Virginia's governor in the mid-1990s. "They were 30 minutes into the debate before Chuck Robb talked issues."

James F. Mulhall, a veteran Capitol Hill hand who started six days ago as Robb's campaign manager, said that Robb had not prepared intensely for the event, and has solid credentials as a politician who is tough on crime.

"Allen is combative, highly partisan," Mulhall said. "His pledge for accuracy lasted a half hour." But, he added, Allen "was very good at the glib lines."

If the Senate race seemed off to an unusually early start, it may be because both Robb and Allen are eager to begin the 10-month battle. One recent statewide poll showed them in a dead heat.

Already, both camps are bracing for a campaign that could be nasty as well as long and expensive. Robb loyalists expect independent, GOP-backed groups to revive reports of Robb's womanizing at Virginia Beach while governor; some Republicans fear that personal questions about the lives of national party leaders such as George W. Bush could splash on their Virginia candidate.

Robb said there was no need to revisit the "excruciating" details already aired about his beach lifestyle of the 1980s.

"That's an area that most people have enough facts and then some to make whatever judgments they think are relevant and . . . move beyond that," Robb said.

Allen, taking his turn on the privacy issue, told the conference of newspaper editors and reporters, "Our campaign, again, is not going to be talking about the past."

"What somebody did, as a public official in personal matters, that's--you know, you all make that decision," Allen said.