Polarized voters, almost perfectly divided between the two parties — and the balance of power hanging on hard-fought, expensive campaigns in a few key areas. It's the story line of the 2004 presidential election, but it's also playing out in the battle for power in state legislatures, where Democratic and Republican control has probably never been so evenly divided.

About 5,800 seats — 80 percent of the national total — are up for grabs in 44 states on Election Day this year. A shift of as few as three seats could alter party control in 25 of the 84 chambers being contested, according to the National Conference of State Legislatures (search). Where chambers change hands, policy could be significantly affected in areas such as education, public safety and health care.

Republicans hope to extend 20 years of steady gains that have erased the Democrats' traditional dominance of state governments. In 2002, for the first time in a half-century, the GOP claimed more legislative seats nationwide than its opponents.

But the edge is slim — about 60 seats out of 7,382 nationally — and Democrats hope they've bottomed out.

"Legislatures are as evenly divided as they've been in history," said Tim Storey, senior fellow and elections analyst at the NCSL. "It's really at a tipping point one way or the other. This election will be a critical marker on whether one party surges ahead" or they're at perpetual parity.

Republicans control both legislative chambers in 21 states, Democrats control both in 17, and control is divided in 11. Nebraska has a unicameral and officially nonpartisan legislature.

But "control" is tenuous in many states. Indiana, Maine, Vermont and Washington are among those where a shift of a handful of seats could switch control of one or both houses. The Oregon Senate is tied at 15, while North Carolina's House ended up 60-60 two years ago, though two Democrats later defected to the GOP.

Of the 11 chambers in 10 states where the NCSL says a party switch is a real possibility, four are currently held by Republicans and five by Democrats, in addition to the shared power in the Oregon Senate and North Carolina House.

Of course, the balance doesn't mean every voter will see a close race.

Most seats in most states are safe for incumbents; generally, only 10 percent to 20 percent of seats in a given state will be competitive, though there are exceptions, said Alan Rosenthal of Rutgers University's Eagleton Institute of Politics.

A wild card is the presidential campaign, which has been accompanied by huge get-out-the-vote efforts by both parties. Oregon, Maine, Colorado and Iowa are among the states where both the presidential race and balance of power in the state legislature are close.

And issues generally considered national can trickle down. Larry Hile, a farmer and Democratic county commissioner running for an open House seat in east-central Indiana, said jobs and health care are on the top of voters' agendas in his district.

"We've basically given up on waiting for Washington, D.C., to help us out with these issues," Hile said. "We're going to have to do it here on the state level."

But generally, local issues determine legislative races. In Pennsylvania, recently passed laws legalizing slot machines will likely be on voters' minds. Major issues in Nevada include a record tax increase passed by the split Legislature last year and "double-dipping" by lawmakers who have held full-time state or local government jobs while also serving in the part-time Legislature.

Another hot issue is outsourcing. Last year, Indiana canceled an outsourcing contract, and several states have taken measures to try to limit the practice.

Legislative power in Indiana's House is precarious — it's been split 50-50 for four of the last 16 years, and Democrats currently hold a 51-49 edge, thanks to one member's 37-vote victory in the last election. Republicans control the Senate there 32-18.

In Montana, where the Republicans' 53-47 House majority is considered vulnerable, GOP leader Roy Brown said voters are concerned about jobs, taxes and education — "the same three issues that happen every session."

Brown, who leads the GOP's legislative campaign committee in Montana, said he thinks having President Bush at the top of the ticket will help Republicans there, and he's confident that hard work will erase the edge gained by the Democrats in recent redistricting.

"Politics in Montana is door to door," he said. "You've got 900,000 people, 100 districts, so each district has 9,000 people in it. You can go to everybody's house in Montana and talk to them. That's what you have to do to win."

Ballot initiatives could also bring voters to the polls, though nobody's quite sure what the effect will be. Bans on same-sex marriage are on the ballot in 11 states, and California has a ballot question on state funding of stem-cell research.

"There's a lot of talk at how evenly divided the country is," Storey said. "You need look no further than the legislative races to have that driven through."