Bipartisan Redistricting Deal Taking Shape : Politics: With work on new Senate boundaries almost done, map drawers are focusing on Assembly district lines. Republicans want--and may get--a chance of controlling the lower house.

Lawmakers drawing the state’s new legislative and congressional districts appeared to be closer Saturday to a deal that could win bipartisan support and, possibly, the signature of Gov. Pete Wilson.

With a Senate agreement all but completed, Assembly map drawers were said to be focusing on a Republican plan to collapse the district of a Bay Area Democrat. That would allow creation of another GOP seat elsewhere and avoid dramatic changes in several other Northern California districts.

“The sights seem to be closing in on Dominic Cortese,” said one Democrat, referring to his colleague from San Jose who seemed to be the most vulnerable of the Assembly’s 47 Democrats.

Several sources said they believed that collapsing Cortese’s district, or that of the neighboring Assembly district of Democrat Byron Sher, would be enough to persuade Republicans that they would have a chance to capture a majority in the Legislature’s lower house in 1992 or 1994.

In the negotiations over new congressional lines, Rep. Howard Berman, a Los Angeles Democrat who is leading the congressional line-drawing effort, spent most of the day in closed-door talks with his Democratic colleagues and Republican negotiators.

A major sticking point, according to Republicans, involved the Democrats’ attempt to create districts for two members of the loose-knit, Los Angeles-based political organization headed by Berman and Democratic Rep. Henry Waxman.

Creating the districts--one tailored for state Sen. Gary Hart of Santa Barbara and one for Assemblyman Burt Margolin of Los Angeles--would give Democrats more seats than their voter registration numbers warrant, Republicans said. The Hart seat would be among the state’s seven new districts. The Margolin seat would be a reshaped version of the district now represented by Democratic Rep. Mel Levine of Santa Monica, who is planning to run for the U. S. Senate.

“They are trying to hang onto the Levine seat. If they want it, they’ve got to give up the Hart seat,” said Republican Rep. John Doolittle of Rocklin, the GOP’s lead negotiator. If Democrats persist, Doolittle said, “it’s a deal breaker.”

But Republicans were far from united on a strategy for the congressional districts. Wilson’s office released a statement from White House Chief of Staff John Sununu, in which Sununu said some Republican incumbents were supporting plans that provide “incumbent protection” instead of addressing the “need for fairness.”

Lawmakers said their current target date for completing the map-drawing is Tuesday. If the job isn’t done by then, said Senate Republican Leader Ken Maddy of Fresno, “We will declare impasse, throw up our hands and go.” Redistricting then presumably would be handed over to the courts.

Wilson has repeatedly vowed to veto any redistricting plan that does not give Republicans a competitive chance to win control of the Legislature and California’s congressional delegation.

The Senate has virtually completed its plan, and Maddy said only technical changes remained before the maps would be ready for Senate action on Monday.

But the Senate, Assembly and congressional plans all will be tied together in a package. And until the last day or two, the Assembly was making little progress. Republicans, who now control 31 seats with two vacancies expected to go their way, want a chance to seize a majority of the house’s 80 districts. They argue that the Democrat-dominated line-drawing process in 1982 robbed them of an opportunity to win a majority for 10 years.

Assembly Speaker Willie Brown (D-San Francisco) already has agreed to eliminate one Los Angeles County district held by Democrats and add one to a heavily Republican corridor in Riverside and San Diego counties. Now, several legislative sources say, Republican negotiators are poised to agree to the plan if Brown will give up one more Democratic seat. Under such a deal, the GOP would be assured of about 36 districts with a chance at perhaps eight more.

Even many Democrats believe that Brown should agree to such a deal, as long as they are not the ones sacrificed for the sake of the remaining incumbents.

The most likely target seemed to be Cortese, a six-term veteran from San Jose. Cortese, who could not be reached for comment Saturday, has considerable wealth from private business ventures and recently got in political hot water for accepting personal favors from a trade association with an interest in legislation.

Assemblyman Tom Hannigan of Fairfield, Speaker Brown’s top lieutenant on the redistricting issue, refused to confirm that top Democrats were about to cut Cortese loose. But he indicated that Republican demands for at least one more district were not unreasonable.

“It may be that what they are arguing for us to do is in fact what demographics dictate we do,” Hannigan said in an interview. He said the Assembly was perhaps 85% of the way to a completed plan that both parties could support. But he added:

“It’s much more difficult from there to the finish line.”

Times staff writers Mark Gladstone and Ralph Frammolino contributed to this story.