NEW ORLEANS, Oct. 20 — Bobby Jindal, a conservative Republican congressman from the New Orleans suburbs and the son of immigrants from India, was elected Louisiana’s governor Saturday, inheriting a state that was suffering well before Hurricane Katrina left lingering scars two years ago.

Mr. Jindal, 36, defeated three main challengers in an open primary, becoming this state’s first nonwhite governor since a Reconstruction-era figure briefly held the office 130 years ago.

With more than 90 percent of the vote counted, Mr. Jindal received 53 percent, above the 50 percent-plus-one threshold needed to avoid a runoff in November. He will be the nation’s first Indian-American governor when he takes office in January.

Mr. Jindal’s victory over a state Democratic party weakened by perceptions of post-hurricane incompetence and corruption was expected, as he has had an overwhelming lead in polls for months. The incumbent, Gov. Kathleen Babineaux Blanco, hurt by stumbles after Hurricane Katrina, did not seek re-election.

The ascendancy of the Brown- and Oxford-educated Mr. Jindal, an unabashed policy wonk who has produced a stream of multipoint plans, is likely to be regarded as a racial breakthrough of sorts in this once-segregated state. Still, it is one with qualifiers attached.

For one thing, he is by now a familiar figure in Louisiana, having made a strong run for the governorship in 2003, though losing to Ms. Blanco. Before that he had held a series of high-profile administrative jobs, including state health secretary at the age of 24, when he earned a reputation for efficiency — critics said cold-bloodedness — for slashing a bloated budget, cutting jobs and lowering reimbursements to doctors.

For another, he did not have the support of a majority of the state’s blacks, about a third of the population, who vote Democratic.

Yet Mr. Jindal, with his decisive victory on Saturday, appears to have overcome a significant racial hurdle that blocked him in 2003, according to analysts: race-based opposition in the deeply conservative northern and eastern parishes of Louisiana that once supported the Ku Klux Klan leader David Duke.

A born-again Roman Catholic, Mr. Jindal made a particular campaign target of these areas, visiting them frequently and bringing his brand of devout Christianity to their rural churches. His social-conservative message — teaching “intelligent design” as an alternative to evolution in public schools, a total ban on abortion, repealing hate-crimes laws — would have been welcome in these areas.

Mr. Jindal campaigned as a cautious reformer, promising a more ethical government, for example, with greater transparency from lobbyists and legislators. His extensive résumé helped him project an image of competence, as did his detailed if conventional policy prescriptions — both evidently appealing to voters here weary of missteps in government since Hurricane Katrina.

But he faces significant challenges. He takes over what is now the nation’s poorest, most uneducated and most unhealthy state.