The Super Tuesday primary may not have settled both party's presidential nominations for the fall, but the voting results in California did provide a clear picture of what will happen politically in Ventura County come November:

It will be the site of a free-spending, no-holds-barred, partisan campaign the likes of which it hasn't seen in two decades.

That was settled with the defeat of Proposition 93, the measure that would have altered term limits. One of the changes it sought would have allowed 22-year legislator Tom McClintock of Thousand Oaks to seek one more term in the state Senate. Since the measure failed, McClintock will now be forced to step down — creating an opening in what will likely become one of the biggest battleground districts in California.

At first blush, it seems incongruous that a district that includes the Ronald Reagan Presidential Library and has been represented for the last eight years by one of the most conservative politicians in the state could now be up for grabs. But even Republicans acknowledge that it will be.

Just Monday, for instance, GOP state Sen. Jim Battin of Palm Springs posted a plea on a Republican political blog asking conservatives to reconsider their hard-core opposition to Proposition 93.

If it failed, Battin warned, several Republican-held seats in the Legislature would be at risk without an incumbent on the ballot. He cited McClintock's seat as a prime example.

Battin also explained why the outcome could be of such great potential consequence: Democrats are just two seats short of controlling a two-thirds majority in the Senate right now, so the loss of even one Republican seat could put at risk the GOP's ability to block all potential tax increases.

The 19th Senate District includes Thousand Oaks, Simi Valley, Moorpark, Camarillo, Ventura, Ojai, most of Santa Barbara County and a small slice of Santa Clarita. It was designed during the 2001 redistricting to favor a Republican, but the GOP advantage was relatively slight from the outset and has diminished over time.

When it went into effect in 2002, there were 31,842 more registered Republican voters in the 19th District than Democrats, giving the GOP a 6.7 percentage point edge. As of two weeks ago, the numerical difference had been cut by more than half, to 14,672, and the edge had been reduced to 3.1 percentage points.

It is one of just three Senate districts in the state in which the two parties are within 5 percentage points of each other in voter registration. The last time such a district became open, the result was a $7.5 million campaign in which the winner prevailed by fewer than 1,400 votes.

The possibility for victory on both sides has attracted heavyweight contenders: former Assembly members who previously represented the two halves of the district. They are Republican Tony Strickland, who represented the conservative half to the east, and Democrat Hannah-Beth Jackson, who represented the more moderate half to the west.

Absent an unexpected development between now and March 7, those two will run unopposed in their party primaries, which will allow them to save resources until the fall. Neither candidate blinked Wednesday when I asked if their combined campaigns would reach the $4 million mark in spending.

As of Dec. 31, Strickland, who launched his campaign early last year, had $540,000 in the bank. Jackson, who didn't get started until fall, had $160,000 in her account. For both, it's just an ante that will be called and raised and raised again by the state parties and independent expenditure groups in the fall.

Both candidates are aware that the only way to survive in a competitive district is to run to the center — to try to portray themselves as moderate and their opponents as extremist.

Says Jackson: "People are looking for more of a dialogue than a stubborn, obstinate, ideological view of the world. We have to compromise; we have to respect different points of view."

Says Strickland: "We're going to have to win Republican voters, independent voters and Democratic crossovers. You don't win these targeted races with only Republican votes."

Competition, rare in California's gerrymandered political world, can be a wonderful thing. The candidates will have to be responsive, will have to appeal to a much broader segment of the electorate than just their respective ideological bases, will have to engage voters, and will be well advised wage issue-oriented, positive campaigns.

The possibility for this kind of high-profile race has been shaping up for some time. Now that Proposition 93 has been defeated, the game is on.

— Timm Herdt is chief of The Star state bureau. Read is blog on politics, "95 percent accurate*," at www.VenturaCountyStar.com/herdt.