Janet—no one seems to call her by the octosyllabic "Governor Napolitano"—is on a first-name basis with Arizonans, but her manner is low-key and businesslike. In an interview over breakfast recently in Washington, exuberance broke through only twice. Once was at the mention of Fife Symington, a Republican whose tenure as Arizona's governor ended in 1997 with a criminal fraud conviction (overturned on appeal) and who is said to be considering a run against Napolitano in 2006. "A lot of what I'm having to do is fix things that he broke," she said. "His policies in the '90s drove us backward, and I would love to have that debate with him." Her grin underscored the word "love."

She was equally animated on early-childhood education, a theme that has emerged as something of a trademark, thanks to her all-day kindergarten initiative. (Before Napolitano, the state financed only half-day kindergarten classes.) "You can really see what happens when you invest in early education," she said. "It gets more kids reading!" The exclamation point was audible.

The governor, 47, likes children and she likes a good fight, and the combination seems to work. If many centrist Republicans are looking to California Gov. Arnold Schwarzenegger these days for hope, centrist Democrats could do worse than look to Napolitano. She is, after all, more popular than the Gubernator himself.

Arizona is a fast-growing, predominantly suburban and rural state—the sort of place where Democrats are often thought to be an endangered species. The population grew by a startling 40 percent between 1990 and 2000. About 185,000 new residents are expected this year. At that rate, two or three more people will have moved to Arizona by the time you finish this article. Between population growth and the latest in a seemingly inexhaustible series of real estate booms, the economy is as hot as the climate. On the whole, it's a good place to be governor.

But not such a good place to be a Democrat. Republicans enjoy a 5-point advantage in voter registration; they control both U.S. Senate seats, six of eight U.S. House seats, and both chambers of the state Legislature. Since Harry Truman, the state has voted Democratic in a presidential race only once, in 1996.

Arizona's Republican Party is a three-part coalition. Libertarians, such as former Sen. Barry Goldwater, and pro-business moderates, such as Supreme Court Justice (and former state Senate Majority Leader) Sandra Day O'Connor, were historically predominant, with religious and other social conservatives as junior partners. In recent years, however, energized social conservatives have shaken up the old order and pushed to the front of the line.

"There are really no unsafe seats in the Legislature," says Democratic state Sen. Ken Cheuvront. With most districts solidly Republican or Democratic, state legislators face their only real fight in the primaries, where partisans and ideologues dominate. In 2004, Cheuvront says, religious conservatives had a particularly good year, unseating several moderate Republicans in the Legislature.

"It is impossible for centrist moderates," says Deb Gullett, a Republican who served in the state House from 2000 to 2004. She quit in 2004, deciding not to put her 11-year-old through a primary challenge in which conservative activists, she says, literally called her a criminal.

If the state's Republican Party is turning to the right, however, the state is not following. "We have a very sizable proportion of independents in this state," says Margaret Kenski, a Tucson-based pollster and political consultant. Her polling, she says, finds "a perfect willingness on the part of Republicans and Democrats alike to cross party lines." Moreover, the state is young (despite its retirement image) and increasingly diverse. Cheuvront adds, "We are moderating as a state because of a huge influx of Californians." Although the battle for the Arizona Republican Party is not over, "If the Religious Right wins out," says Bruce Babbitt, a former Democratic governor, "it could open a lot of space for Democrats."

Into this space walked Napolitano. Or, rather, squeaked. After five years as a federal prosecutor and four as state attorney general, she won the governorship in 2002 by fewer than 12,000 votes, despite outspending an opponent who was battered in the primaries. Yet she has managed to parlay a weak mandate into a strong position. "She hasn't made any major mistakes," Kenski says. "And she has pursued and played well a Clintonian triangulation strategy."

Democrats and also Republican women—a key swing constituency, among whom Napolitano is popular—like her focus on education and children. The kindergarten initiative has gone down well with suburban moms and leaves Republican legislators, who have resisted it, on the defensive. "They end up almost unwittingly looking more concerned about the budget than the welfare of kids," says Lisa Graham Keegan, a former Republican state superintendent of public instruction.

When the Republican-controlled Legislature recently rejected Napolitano's proposed increases for all-day kindergarten, child care subsidies, child protective services, and a new medical school in Phoenix, she vetoed the budget 20 minutes after it was delivered to her office. Liberals and Democrats liked that.

Economic conservatives and business interests (whom she courts—no anti-corporate populism here) like her opposition to tax increases. "People are strapped," she said in the interview. "They don't want to hear about raising taxes." The Legislature seeks broad tax cuts, to the tune of hundreds of millions of dollars a year; Napolitano parries with smaller, targeted tax cuts (mostly for business) costing in the tens of millions. To scowls from Republican advocates of school vouchers, she frames her all-day kindergarten initiative as "one of the largest school-choice programs in state history," because participation is voluntary. In her State of the State address this year, she boasted of attacking "government waste and inefficiency." Cheuvront, the Democratic state senator, says that Napolitano "sounded more like a Republican governor than a Democratic governor."

Her exposed flank is on the cultural Right. Republicans are not above pointing out that "she doesn't have a family," as Senate President Ken Bennett told reporters in January. (Reports the Tucson Citizen, "Told that it sounded mean-spirited to criticize Napolitano because she is single and childless, Bennett dryly replied, 'I apologize if it did'—in a tone that clearly indicated he knew it and didn't care.")

Though Napolitano is no social conservative, she gives the cultural Right little ammunition. Her background is in law enforcement; her budget this year reserved most state pay raises for public-safety and corrections workers; she has proposed expanding the prisons; in February, she came out against an effort by the American Civil Liberties Union to remove a Ten Commandments monument from the state Capitol grounds. She is an outspoken critic of Washington's (read: the Bush Administration's) "timidness" on homeland security and border control. She says she is pro-choice but not for abortion: "It's about who decides, you or 90 other people." When Republicans bait her with gay marriage, which they hope to put on the ballot with her next year, she just says she opposes it and moves on.

"That's all I'm going to say" on the subject, she declares. Her advice to fellow Democrats: "Don't fight on the other side's turf all the time. Quit defining 'values' as abortion and gay marriage."

Earlier this year, her most formidable potential Republican challenger, U.S. Rep. J.D. Hayworth, declined the race. A March poll by Northern Arizona University's social-research laboratory found Napolitano leading her remaining potential 2006 rivals by margins that could only be called ridiculous; the closest challengers were 29 points behind. Her approval rating was 70 percent, almost twice as high as the Legislature's. By way of comparison, Schwarzenegger's approval rating in California was 54 percent in February.

The Republicans, frustrated by their lack of traction, seem to be reacting by moving further right. This month, the Legislature hurried to pass a bill allowing pharmacists to refuse to dispense abortion-related medications. Napolitano vetoed it last week.

"One of the things I do," she says, "is help bring things back to the center." She expects her lead to narrow, and doubtless it will. Arizona is still a Republican state, and Napolitano is still a Democrat. Even so, her political ju-jitsu shows what Democrats can do, even in Republican country, when they can find and fill a hole in the political center. Fortunately for them, Republicans—in Arizona and in Washington—are doing their best to provide one.

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