Three heavyweight conservatives have enlisted with the campaign of Rep. Pat Toomey (search) as he seeks to oust incumbent Sen. Arlen Specter (search) in Pennsylvania's bare-knuckles Republican primary.

Former federal appeals judge Robert H. Bork (search) — whose 1987 U.S. Supreme Court nomination was thwarted, in part, by Specter — said Monday that his endorsement stems mainly from fear that Pennsylvania's senior senator will chair the Senate Judiciary Committee next year if he wins re-election.

Bork will formally endorse Toomey at a Pittsburgh fund-raiser Wednesday, the eve of Specter's planned statewide two-day campaign tour. In the next six weeks, 2000 presidential hopeful Steve Forbes (search) and former U.S. Attorney General Edwin Meese (search) III also are expected to headline Toomey fund-raisers in Philadelphia and Harrisburg.

"It's quite clear that he doesn't think that judges ought to stick to the original understanding of the Constitution, but up to other considerations — primarily political and social," Bork said of Specter.

Specter "has a record of being quite liberal for the first and early part of his senatorial term," Bork said. "And then as he gets near election time, he's beginning to give some votes that will please conservatives."

Responded Specter spokesman William Reynolds: "Judge Bork apparently has a different opinion on the issue than President Bush, who recently stated during a trip to Pittsburgh that he looked forward to working with Sen. Specter as chairman of the Judiciary Committee."

Bork, criticized as an anti-labor and pro-business federal judge, maintained throughout the Senate hearings that there is no general right of privacy in the Constitution. Specter was the lone Republican on the Judiciary Committee to vote against Bork, arguing that the judge's ideas on equal protection and dissenters' rights might place him outside the mainstream of judicial thought.

Also supporting Specter is former Sen. Paul Laxalt, R-Nev., who describes himself as "an original Reaganite" and noted, in a Nov. 19 letter of endorsement, "the many critical occasions when conservatives could count on your support."

But Forbes calls Toomey  "U.S. Rep.Courageous" who "is a tireless and effective advocate" on issues like tax-cutting, Social Security reform, school choice vouchers and opposing abortion.

Specter launches his statewide tour Thursday with stops in Philadelphia, Harrisburg, Pittsburgh and Erie. He travels to State College, Wilkes-Barre and Allentown on Friday.

The primary is April 27.