Jim Dantona, the Simi Valley political consultant who lost his race for county supervisor by less than 900 votes last year, announced Monday that he will seek the Democratic nomination for the 19th state Senate District next year.

"I'm off and running," he said. "We're ready to move."

Dantona, 59, said that papers to incorporate his campaign committee have been dispatched to Sacramento and that the committee should be active by the end of the week. Formation of the committee is not a certain declaration of candidacy, but does allow the candidate to begin accepting campaign contributions.

The district, which includes southern Santa Barbara County and all of Ventura County except Oxnard, Port Hueneme, Santa Paula and Fillmore, is now represented by Sen. Tom McClintock, R-Thousand Oaks.

McClintock will be termed out in 2008 unless a ballot initiative on the February ballot passes. That measure would allow the incumbent to seek a third term.

Dantona said he is operating under the assumption that the law will not change. If voters approve the change, he said he might re-evaluate the decision. "I will look at that come February," he said.

If the seat in fact becomes open, it will likely be one of the most contested and expensive Senate races in the state, as it is one of only a few that is potentially competitive. Registered Republicans outnumber registered Democrats in the district 41 percent to 36 percent, and more than 18 percent are independents.

Former Assemblyman Tony Strickland of Moorpark is seeking the Republican nomination and already has nearly $400,000 in the bank for his campaign.

Another potential candidate is former Democratic Assemblywoman Hannah-Beth Jackson, who said Monday that she expects to make a decision by early October.

Jackson said she is unconcerned about a potential Democratic primary battle and noted that the candidate filing period does not open until February.

"Nothing's written in stone," she said.

Dantona said he is committed to the campaign. He said he spoke to Jackson over the weekend and "let her know that I'm in the race for keeps. You'll see that in the end, there will be one Democrat running."

Dantona said that although voter registration favors a Republican, the district's high percentage of independents suggests that voters will be receptive to a centrist candidate from either party.

Describing himself as "a centrist Democrat," Dantona said, "People are tired of candidates who play to one out-of-the-mainstream group."

Local Democrats contend that Dantona could fare well in the Republican-leaning district. They note he narrowly lost the supervisor's race in a district in which Republicans enjoy a 47 percent to 31 percent edge in registered voters.

Dantona said he intends to campaign on such issues as the environment, healthcare and "government fiscal responsibility."