The newspaper ad portrays a magnifying glass over the words "advice and consent" and proclaims in large type, "Why the U.S. Senate should take a very close look at Robert Bork."

"In the end, a Supreme Court justice is not supposed to be a White House 'team player,' " says the ad by the liberal activist group, People for the American Way, that is to run in newspapers in Washington, New York, Chicago and Los Angeles this week and next.

Bork's "judicial philosophy will restore government by the people," declares a radio spot by the conservative Coalitions for America that is scheduled to begin running on two local stations today. "Listen to the reasonable things being said about Judge Bork," says the ad, quoting from Gov. Mario M. Cuomo of New York, a Democrat, and from editorials in The Washington Post, The Wall Street Journal and The (Baltimore) Sun.

One month after President Reagan nominated Robert H. Bork for a vacancy on the Supreme Court, liberal and conservative groups are unveiling media campaigns, preparing in-depth studies of Bork's record as a federal appeals court judge and blitzing their members with fund-raising and letter-writing appeals.

Their initial efforts will focus on members of the Senate Judiciary Committee and will then target two dozen considered swing votes when the nomination reaches the Senate floor.

"We're in triple gear," said Nan Aron, executive director of Alliance for Justice, a liberal lobbying group that opposes the nomination. "We've now constructed much of the case {against Bork}, and it's a matter of taking that case out to the states and sharing our information with people."

The group is to hold a meeting today about "mobilizing the campus" to fight the nomination. At the American Bar Association convention in San Francisco next week, the Alliance will sponsor a forum on Bork with the Federation of Women Lawyers.

Conservative groups have also been preparing for battle.

Concerned Women for America plans to run newspaper ads Sunday in Alabama and Pennsylvania, home to two Senate Judiciary Committee members, Howell Heflin (D-Ala.) and Arlen Specter (R-Pa.), urging readers to send mailgrams in support of Bork. If the ads generate a good response, said spokesman Rebecca Hagelin, the group will purchase space in newspapers in 25 states whose senators are considered swing votes.

"The activating that we said we were going to do seems to have happened," said Daniel Casey of the American Conservative Union." In Senate offices, he said, "the pro-Bork mail is catching up to the anti-Bork mail, which is pretty significant when you figure that it's a lot easier to oppose than to support."

Although Reagan in a speech last week emphasized similarities between Bork and the man he has been nominated to replace, retired justice Lewis F. Powell Jr., the mailings sent out by conservative groups stress that putting Bork on the court could make a difference.

"We are standing at the edge of history," the Rev. Jerry Falwell, Moral Majority leader, wrote in a recent letter. "Our efforts have always stalled at the door of the U.S. Supreme Court," and Bork's nomination "may be our last chance to influence this most important body."

Two new studies should provide ammunition for both sides.

One study, to be released Thursday by the Public Citizen Litigation Group, a public-interest law firm, examines Bork's decisions as a judge on the appeals court here.

Although the group has never before conducted such a review, said director Alan B. Morrison, "This is a different case . . . {Powell} has been a swing vote on the court for a number of years."

On the other side, the Center for Judicial Studies, a conservative think tank, later this month will publish its analysis of Bork's opinions, according to James McClellan, the group's president.

Meanwhile, organizations that do not normally take positions on judicial nominations are finding themselves embroiled in the fight over Bork.

The governing board of Common Cause voted Saturday to oppose Bork, the first Supreme Court nominee on which the group has taken a position, and the American Civil Liberties Union board of directors will consider a similar move later this month.

"The record of Robert Bork convinces us that he cannot judge fairly, constitutional claims to liberty and equality," the Common Cause board said in a resolution. Common Cause Chairman Archibald Cox, who was fired by Bork from his position as Watergate special prosecutor in 1973, did not participate in the discussion of the resolution because of their previous connection.