The battle over the SAG-AFTRA merger has heated up with both sides grabbing as much heavy-hitting star power as possible.

Proponents of the proposed SAG-AFTRA merger trumpeted endorsements Tuesday from Nicolas Cage, Kevin Costner, George Clooney, Jane Fonda, Tom Hanks, Anjelica Huston, Martin Sheen and Kevin Spacey. And they pledged more big names will get on board soon.

The move is the lastest gambit by the unions’ leaders to persuade the 98,000 SAG members and 77,000 AFTRA members to vote up the deal. At least 60% of voters from each union must approve for the deal to go through, creating an umbrella union with affiliates for actors, broadcasters and recording artists.

Other notables among the 200 endorsers: Kevin Bacon, Angela Bassett, Jackson Browne, James Cromwell, Richard Dreyfuss, Janeane Garofalo, Danny Glover, Jane Kaczmarek, Eriq La Salle, Marlee Matlin, Willie Nelson, Lynn Redgrave, Cliff Robertson, Bradley Whitford and Moon Zappa.

Merger backers have contended that the unions need to combine to enhance their clout at the bargaining table against the mega-congloms, avoid jurisdictional disputes and operate more efficiently. Opponents have argued that a merger won’t add to the power of actors but will instead create more bureaucracy and cause SAG to lose its autonomy.

SAG and AFTRA have refused to use the word “merger” in campaigning for the deal, opting instead for the phrase “consolidation and affiliation.” The tactic reflects the desire of the unions to highlight differences in approach from 1999’s proposed merger, which was defeated after receiving only 46% support from SAG voters.

SAG prexy Melissa Gilbert has been actively campaigning for the deal while secretary Elliott Gould and treasurer Kent McCord have opposed it. Among former SAG prexies, Patty Duke, Richard Masur and William Schallert have endorsed the merger; William Daniels, Charlton Heston, Howard Keel and Kathleeen Nolan are against it.

Big names talk

SAG voters have tended to be heavily swayed by high-profile members in recent elections. For example, last fall’s voting for Hollywood board members was dominated by recognizable names with voting led by James Cromwell, Noah Wyle, Mike Farrell, Shelley Fabares, Richard Dreyfuss, Morgan Fairchild, Mariette Hartley, Jane Kaczmarek, William Schallert, Bruce Boxleitner and Richard Crenna.

A-listers have tended to avoid becoming involved in SAG politics, though Spacey and Cage made six-figure donations to the relief fund for striking actors during the 2000 commercials strike. Spacey has also been active in promoting SAG Global Rule One and was the lead speaker at the news conference launching the policy.

Key high-profile names among opponents include Tom Bosley, Michael Chiklis, Dom DeLuise, Frances Fisher, Robert Forster, Estelle Getty, Valerie Harper, Ed Harris, Charlton Heston, Holly Hunter, Sally Kirkland, Diane Ladd, Amy Madigan, Ed McMahon, Ricardo Montalban, Esai Morales, Rob Schneider and Shelley Winters.

Each member has received a packet containing over 100 pages of information. The unions will send out ballots on June 9 with a June 30 deadline for return.

Each of the 44,000 thesps who are dual cardholders will receive two ballots – one for each union.

SAG’s membership has been unpredictable in its voting in recent years. It chose Daniels over Masur, who was seeking a third term in 1999; it then twice voted for Gilbert over Harper, who was backed by Daniels; and it voted down a revamp of its agency franchise agreement last year even though that led to giving up oversight of talent agents.