SACRAMENTO ? In the heat of a Central Valley summer, with midday temperatures over 100 degrees, Democratic legislators are preparing to test their working partnership with Republican Gov. Arnold Schwarzenegger in the ultimate crucible by asking the voters to relax the limits on their time in office.

They hope that by joining forces with the governor on a wide range of big issues, they will gain enough credit that their constituents will let them stay in office beyond the strict time imposed by a 1990 term-limits initiative.

But before they take the new limits to the polls in an initiative planned for February’s presidential primary, the Legislature and governor must agree on a redistricting reform that will take line-drawing out of politics and put it in the hands of a nonpartisan commission. Schwarzenegger has made approval of the redistricting reform the condition for his supporting the term-limits initiative.

And that is where it gets complicated for the Democrats. Schwarzenegger wants the proposed redistricting commission to have authority to revise congressional lines, as well as legislative. And that prospect alarms the powerful California contingent in Washington, led by House Speaker Nancy Pelosi. Comfortable in the seats they hold under a five-year-old insiders’ deal that locked in both parties’ incumbents, these lawmakers are threatening to raise millions to fight any redistricting reform that includes them.

The looming political impasse tests the partnership that has grown up this past year between Assembly Speaker Fabian Nunez, a liberal Democrat, and Schwarz-enegger. Nunez and his fellow Democrats treated Schwarzenegger with contempt when the bodybuilder and Hollywood star showed up in Sacramento as the surprise winner of the recall election against Democratic Gov. Gray Davis. Schwarzenegger famously derided them as “girly men,” but when he tried to skip the Legislature and pass the heart of his program by calling a special election on four sweeping voter initiatives, he was met with complete failure.

After that, a chastened Schwarzenegger reached out to Nunez and Senate leader Don Perata, inviting them into his smoking tent in the Capitol courtyard and cutting deals on big bills.

The turnabout revived Schwarzenegger, setting the stage for his easy re-election last November, and boosted the even-lower ratings suffered by the Legislature. And now what he calls “post-partisan” politics has become the dominant culture in this capital – a shiny contrast to the continuing political warfare of Washington.

Last year, for the first time since 2000, the budget was signed by the June deadline set in the state constitution. Last week, the Legislature’s deadline passed with the spending plan still in dispute, but negotiations are nearing an end. And plans are ready for a second round of infrastructure bonds, following the approval of major transportation and water bonds last year and a $3 billion state investment in stem cell research.

This year, Schwarzenegger has signed landmark legislation to satisfy a court order to expand prison facilities and has gained authority for limits on carbon emissions from cars and trucks that go beyond anything enforced elsewhere in America, making California a model in the battle against greenhouse gases.

The governor’s bold proposal in January to provide health insurance for every family in California has run into a buzz saw of opposition from hospitals, doctors and businesses – all of whom would be required to help finance the coverage. But Democrats in both the state Senate and Assembly have responded with major health care bills of their own. Nunez is backing a version that he says would mean coverage for seven out of 10 uninsured Californians.

Before the session ends in August, chances are that some significant progress will have been made on that front. The hope is that this will set the stage for a vote Feb. 5 on a term-limits initiative, for which the signature-gathering is now almost complete. The current limits – three two-year terms in the Assembly, and two four-year terms in the Senate – have produced such rapid turnover that key committees have been headed by freshmen with little knowledge of the issues they are handling.

The proposal that will go to the voters would limit a member to 12 years total service, but allow him or her to do all of it in one chamber. If approved in February, many term-limited members could file for re-election in the June state primary, with good prospects of continuing their service.

But the dispute on including the congressional delegation in the redistricting reform could spoil the picture – a visitation of Washington’s partisan politics that the California Legislature and Schwarzenegger would like to keep 3,000 miles away from their happy home.