Armed with the latest technology and elbowing for even the smallest partisan advantage, state lawmakers and their number-crunching deputies are toiling to redraw the nation's congressional and legislative maps, a technical exercise known as redistricting.

The process is numbingly arcane. The stakes are huge.

The outcome will chart the course of campaigns for a decade or more, starting in 2002. Careers will be made, ambitions thwarted. Control of the House of Representatives, now Republican by a hair, could be affected by a jot here or a squiggle there.

"You can change candidates. You can change messages. You can change the amount of money you spend" on a campaign, said Tom Hofeller, one of the Republican Party's chief redistricting strategists. But for 10 years, "the political boundaries [stay] constant."

Most analysts foresee a slight GOP edge once the process is completed next spring, as Republican gains in Pennsylvania, Michigan and Ohio are offset by losses in California, Georgia and a handful of other states.

The wild card is Texas, where the courts will likely end up drawing the boundaries. Experts say Republicans could pick up anywhere from zero to seven seats in President Bush's home state, depending on what judges decide. That could be the difference between the big gains Republicans forecast nationally and the wash that Democrats predict.

If there is one certainty surrounding a process otherwise rife with uncertainty, it is that most--if not all--of the remap plans will provoke some sort of court fight.

"Anybody can file a lawsuit in America, and redistricting will prove that," said Don McGahn, an attorney for the National Republican Congressional Committee.

California Makes Gain in House

In California, redistricting has been largely set aside as lawmakers focused on the electricity crisis and state budget impasse.

While input has been solicited at a series of public hearings and various proposals are circulating, the real work will be completed behind closed doors during a few frenzied weeks starting in late August, when lawmakers return from their summer break. The job must be completed by Sept. 14, when the legislative session ends.

California is gaining one House seat as a result of population shifts over the last decade, raising its biggest-in-the-nation delegation to 53 members. Currently Democrats outnumber Republicans, 32 to 20.

Several involved in the line-drawing process say lawmakers are discussing a plan to protect most incumbents and give Democrats the state's extra congressional seat. But the storm surrounding Rep. Gary A. Condit of Ceres has complicated things; his once-safe Democratic seat is no longer so.

Democrats, who control redistricting in California, may end up going after several GOP incumbents in hopes of offsetting seats lost elsewhere across the country.

"Obviously there will be some pressure to stretch the number" of targeted Republicans, said a Democratic strategist involved in the remap process.

As complex as redistricting is, certain fundamentals apply.

All 50 states are granted one House seat. The other 385 are divided by population. The Constitution requires a national head count every 10 years to adjust the allotment of seats to reflect population changes. The theoretical notion is that every member of Congress should represent roughly the same number of people. (Each state has two U.S. senators, regardless of population.)

As a result of last year's census, 12 House seats are shifting among 18 states. The big losers are the Northeast and Midwest, where New York and Pennsylvania each lost two seats. Connecticut, Ohio, Michigan, Illinois and Indiana also lost a seat apiece.

The winners are largely the Sun Belt states that saw large population gains over the last 10 years. Florida, Texas, Georgia and Arizona picked up two seats each. Nevada, North Carolina, Colorado and California gained a seat apiece.

Hostile Shifts in Friendly Districts

Now it is up to state lawmakers to redraw congressional and legislative boundaries to account for the flux, a power that can summon the best and worst of human nature: loyalty, vengeance, generosity and opportunism.

Both major parties hope to exploit the process to their greatest advantage. That means drawing as many friendly districts--ones packed with reliably supportive voters--as reasonably possible.

Certain legal standards govern the exercise, aiming to protect minority interests and guard against the most outlandish acts of partisanship. But even so, lawmakers are fairly free to undermine the other party by redrawing districts to be as hostile to their incumbents as possible. In some cases, they may erase a House member's home turf altogether.

Both things happened in Michigan this year, where Rep. David E. Bonior--the No. 2 man in the Democratic leadership--opted to run for governor after being shoved into a heavily Republican district under a plan crafted by GOP lawmakers.

Separately, the durable Rep. John D. Dingell was thrown into a Detroit-area district with a fellow Democrat, Rep. Lynn N. Rivers, which will effectively eliminate one or the other from office. Dingell is the longest-serving member in the House of Representatives, first elected in 1955.

Angry Democrats sputtered about a "betrayal of the Michigan people." But their best hope may be trying to avenge the losses elsewhere.

Overall, Democrats hope to come out even in redistricting nationwide. Strategists are banking on the fact that the party in the White House almost always loses seats in the midterm elections, which is why the GOP is hoping to shore up its prospects in 2002 with a more favorably drawn map. A loss of just six seats would cost Republicans control of the House.

Yet while the imperative is the same everywhere--grab all the seats you can--the redistricting process varies from state to state.

Seven have just a single congressional seat, meaning no adjustments are required. In six others, independent overseers handle the redrawing of lines.

In most of the rest, different parties control either one legislative chamber or the governor's office, resulting in effective veto power over the most egregious partisan mischief.

The major exceptions are California, Georgia, Maryland and North Carolina--where Democrats are in control--and Florida, Michigan, Pennsylvania and Ohio--where Republicans are in charge.

Republicans in Better Position This Time

From the national perspective, Republicans enter this round of redistricting far better off than 10 years ago.

GOP governors outnumber Democrats, 29 to 19. Republicans control 18 state legislatures, compared with 16 for Democrats.

Seen another way, Democrats the last time had uncontested power over line drawing in 172 congressional districts across the country, compared with just five for Republicans. This time, the number is more even, with Democrats holding functional control over 135 seats and Republicans, 98.

But the biggest change, of course, is the rough parity of the two parties on Capitol Hill. "With a close House," said the GOP's Hofeller, redistricting "is not an academic matter."

Ten years ago, Democrats had a 100-seat majority as map-making got underway. But the GOP took control of the House in a 1994 landslide, in part because Democrats bungled redistricting.

Party leaders in Georgia, for instance, set out to eliminate nemesis Newt Gingrich by forcing the GOP incumbent to run in a newly drawn district packed with Democrats. In the process, however, a number of Democratic incumbents had their districts weakened.

The upshot: Democrats lost several seats in Georgia and Gingrich, who survived, became House speaker after the Republican takeover.

Democrats "now understand it's very important we work together as a group," said Rep. Martin Frost of Texas, the head of IMPAC 2000, which is coordinating the party's national redistricting strategy. "We've seen what happens when we don't."

Still, strategists in both parties struggle against attitudes that can best be described as "me first, party second." That is because, for all the focus on the big picture, redistricting at heart is a deeply personal matter for members of Congress. For some, it even becomes a matter of political life or death.

House members used to being on the receiving end of blandishments suddenly find themselves courting the favor of home-state legislators, who have their own self-interests--perhaps a future seat in Congress--to consider.

Some vulnerable incumbents count on old friendships to see them safely through. Others curry favor with campaign contributions. In New York, which is losing two seats, Democratic Reps. Gary L. Ackerman and Maurice D. Hinchey have hired lobbyists to plead their cases in Albany, the capital.

Improbably enough, Rep. Thomas M. Davis (R-Va.), the head of the GOP's national redistricting efforts, has even had opposition lawmakers plead their cases to him.

"I've had Democrats come up to me saying, 'I'm being thrown in with another Democrat. Can you help me?' Or, 'I just bought a house and plan to retire in Washington. Can you help me?' "

But business is business, Davis said. "This is very hardball inside politics. It's all partisan. Nothing personal."