Hart Won’t Run in 1990 Against Lagomarsino : Politics: There will not be a repeat of last year’s heated, $3-million congressional race. Gary K. Hart decides to seek reelection to the state Senate.

California state Sen. Gary K. Hart, who came within 4,000 votes of unseating veteran Rep. Robert J. Lagomarsino (R-Ojai) last year, will announce today that he will not seek a rematch in 1990.

The Santa Barbara Democrat will end months of speculation that he would oppose Lagomarsino again by declaring his intent to run for a third four-year term in the state Senate next year.

“The many challenging opportunities at the state level balanced against the demands of another difficult, time-consuming and expensive congressional campaign so soon after the last one have led me to decide” not to seek election to Congress in 1990, Hart said in a statement prepared for release today.

The bitter 18th District race--pitting a charismatic liberal against a popular conservative incumbent--was the nation’s second-costliest congressional contest last year, with the two sides spending about $3 million.

Hart, 46, who chairs the Senate Education Committee, is expected to weigh another congressional bid in 1992, after new district boundaries are drawn, said a close Democratic ally who asked not to be identified. If Hart is reelected next year as expected, he could run for Congress in 1992 without giving up his Senate seat if he lost.

“Reapportionment is such a big question mark that it makes any kind of decision a bit chancy,” the Hart confidante said. “It’s such a close congressional district as it is that major changes in reapportionment might make it unwinnable for a Democrat, even an incumbent, in 1992. On the other hand, it could be split in half,” with a Ventura-based district carved out for Lagomarsino and a heavily Santa Barbara district created for Hart.

The governor and state Legislature will redraw congressional districts following the 1990 Census. California is expected to gain four to six seats.

Lagomarsino, 63, a 16-year incumbent, would not comment on Hart’s plans, said John Dogherty, the Republican’s senior aide.

The current edition of Roll Call, a weekly Capitol Hill newspaper, included a rematch between Lagomarsino and Hart among its list of the potentially hottest 1990 House races. It said pundits predicted that each candidate would have spent more than $2 million. Hart spent $1.55 million in 1988; Lagomarsino, $1.47 million.

Although Lagomarsino’s Republican-leaning district and Hart’s moderately Democrat state district are considered potentially competitive, neither incumbent is expected to face serious opposition in the wake of Hart’s decision.

No one has filed with the state Fair Political Practices Commission to oppose Hart. His 19th Senate District extends from Santa Barbara through Ventura, Oxnard and Port Hueneme to Topanga and part of Woodland Hills.