Virginia Democratic gubernatorial candidate Andrew P. Miller, in his sharpest attack to date, has accused Democrat Henry E. Howell and Republican Lt. Gov. John N. Dalton of entering an "odd, unholy alliance" to defeat him in the state's June 14 Democratic primary.

In a speed to his campaign workers in suburban Richmond on Tuesday night, Miller charged that "the word hs been passed in some Republican chairmen to produce a Howell vote" by urging Republicans to enter the Democratic primary and vote for Howell.

Both Howell and Dalton yesterday issued strong denials of Miller's charges. Howell said Miller "is working too hard and has lost track with reality" and Dalton called Miller's charge "an act of desperation," born of a floundering campaign.

"It's a bunch of baloney," snapped Dennis Peterson, communications director for the Virginia Republican Party.

Since Virginia does not have party registration, any voter in the state can, unless challenged by a Democratic Party poll worker, cast a ballot in the primary. This possibility frequently has prompted speculation that large numbers of Republicans might enter the primary this spring to vote for the more liberal Howell in hopes that he would be easier for Dlaton, the expected Republican nominee, to defeat in general election.

Republicans, who are not having their own statewide primary, will choose their gubernatorial candidate at a convention in Roanoke on June 3 and 4.

Despite Miller's charges, numerous Virginia political figures with experience in statewide campaigns repeatedly have said in interviews that they believe the possibility of a significant Republican crossover is remote. They have said it is Miller, rather than Howell, who is most likely to benefit from a substantial turnout of Republicans and conservative Democrats who often vote Republican in general elections.

"It seems to me that Mr. Miller very much wants conservatives and [PARAGRAPHS ILLEGIBLE]

In his speech, Miller was even critical of Howell's accommodating style, criticizing Howell for telling a Chesa-Republicans to enter the primary and vote for him to save him from defeat," Dalton said.

Miller, a former state attorney general, said he saw the issue differently: "I call it cynical manipulation," he said. "It works like this: If you can't nominate a winner, make sure the other side nominates a loser."

Calling Howell "the candidate of peake audience that "he and Andy Miller are more alike than different."

Miller contended that that is not true, "The series of debates just completed dramatically illustrated the difference on the issues between the candidates . . ." he said.

"My opposition to collective bargaining for public employees, my solid support for right-to-work (laws), my specific plan to prevent higher taxes, my record of positive action rather than talk on utility reforms - all stand in marked contrast to Mr. Howell's positions and record," he said.

A spokesman for Dalton said yesterday that both Dalton and Gov. Mills E. Godwin, himself a former Democrat, have publicly urged Republicans not to vote in the primary.

The last time a major Republican official urged such a course was in 1949, when conservative John S. Battle was fighting for the Democratic nomination for governor against the liberal Francis Pickens Miller - the father of the man who made the Tuesday's Republican crossover charge.