Right, center square off in the O.C.

In the conservative corner is state Senate Minority Leader Dick Ackerman, who has already lined up the support of prominent elected officials in Southern California and Sacramento. Challenging Ackerman for the GOP nomination is Marilyn Brewer, a former state legislator with ties to the New Majority, a band of wealthy local Republicans unhappy with the party’s right-wing tilt, particularly on social issues.

Southern California Republicans believe the congressional race will show whether Orange County is still a conservative bastion or has followed the lead of Gov. Arnold Schwarzenegger (R) and adopted a more libertarian bent.

Ackerman is the early favorite, thanks in large part to his fundraising prowess. He raised $100,000 within a day of Cox’s nomination and has connections to a large base of potential donors. Stretching along the coast from Newport Beach to Dana Point, the district is one of the most affluent in the nation.

The district’s strongly Republican leanings and upscale culture make it a prized seat for ambitious GOP politicians. When Cox first won the seat in 1988, he prevailed over 13 other Republicans in a heated primary.

While the number of candidates running is almost certain to swell in future weeks, several would-be candidates have taken a pass on the race and are backing Ackerman. His supporters include three state legislators and influential County Supervisor Bill Campbell, who were expected seriously to consider running.

Their decisions may be strategic, as they bide their time and support the 62-year-old Ackerman with the knowledge that, in the words of one state legislative aide, “he’s not going to be there forever. They’ll have their chance to run for this seat again.”

Though Brewer is likely to have the financial resources necessary to mount a serious campaign, it remains to be seen whether she can drum up the support necessary to prevail over Ackerman in a head-to-head contest.

The 48th District “has a history of electing solidly conservative candidates,” said Dan Schnur, a veteran California GOP consultant who also teaches political science at the University of California-Berkeley. “Orange County’s demographics are changing, but there’s no doubt that conservatives still outnumber moderates in this district.”

The prospects of Brewer or any other centrist candidate would be greatly enhanced should the conservative vote split among several candidates. Brewer benefited from such a phenomenon in 1994, when she was considered a long shot to win the Republican primary for state assembly but narrowly prevailed among a field of conservatives.

The format of the election makes such a scenario possible. The special election to fill Cox’s seat is likely to occur in November or December, depending on when Cox formally steps down, and features all candidates running against each other with the top vote-getter in each party advancing to a runoff if no candidate receives a majority. A crowded Republican field raises the prospect of a candidate prevailing in the primary with a fairly small chunk of the vote.

Two familiar Hill Republicans, ex-Reps. James Rogan and Bob Dornan, are both considered potential candidates who could compete for conservative votes. Rogan, who represented a Pasadena-based district until losing to Rep. Adam Schiff (D) in 2000, moved to Orange County recently and has privately voiced interest in getting back into politics.

A Rogan spokesman described speculation that he would enter the race as premature, since Cox still must be confirmed by the Senate, but confirmed that he is considering running.

The outspoken Dornan, who mounted an unsuccessful primary challenge to Rep. Dana Rohrabacher (R) last year, could not be reached for comment but is widely considered a likely candidate for any congressional vacancy in Orange County. Like Rogan, he could capitalize on high name recognition and popularity among activists to draw a substantial number of votes.

In addition, the district features a handful of potential candidates with the personal wealth to finance their own bids. At least one, former state Sen. John Lewis (R-Orange), appears poised to jump in. Lewis, who amassed a staunchly conservative record over the course of two decades in the state Senate, has closer ties to grassroots conservatives than Ackerman does.

Political neophyte Cassie De-Young is another independently wealthy Republican testing the waters. DeYoung is believed to have commissioned a poll over the weekend to gauge her potential support, as well as that of the other probable candidates.

Lewis and DeYoung both plan to stress their consistent opposition to building an international airport at El Toro, a decommissioned Marine air base in the district. Brewer and Ackerman are considered to be more open to the possibility of locating an airport there, though recently Ackerman has taken a stronger anti-airport stance.

The issue is a familiar one in Orange County politics. Many residents fear that an El Toro airport would create noise problems and exacerbate local traffic congestion.

Because the district is one of the most Republican in the state, whoever gains the GOP nod is all but assured of winning the seat. On the Democratic side, speculation has centered on University of California-Irvine political science professor John Graham, who has challenged Cox in the past three election cycles, garnering 32 percent of the vote in 2004.