Neel Kashkari, who oversaw the U.S. Treasury's much-maligned Troubled Asset Relief Program during the financial crisis, said he is leaving Pacific Investment Management Co. to consider running for public office in Democrat-heavy California, as a Republican.

"As I look at California, there are huge problems," said Mr. Kashkari in an interview, pointing to the state's budget troubles, weak job market and problem-plagued public schools. "These challenges are huge but they're of our own making--so they are within our capacity to solve," he said.

Mr. Kashkari was hired by Pimco in 2009 to help turn the big bond-fund company into a player in equity funds. Since then, the unit of Allianz S.E. (ALIZF, AZSEY, ALV.XE) has launched six new stock mutual funds.

Building an equity portfolio has been slow going. The six funds had about $3.6 billion from U.S. investors, according to research firm Morningstar, and $10 billion in all, according to Pimco, including money from institutions and foreigners that Morningstar doesn't tally. That is less than 1% of the $1.9 trillion that Pimco manages.

The performance of funds Mr. Kashkari launched has been spotty. All six funds lagged behind benchmarks assigned by Morningstar in 2012, using the institutional class of shares as the metric. Mr. Kashkari said the funds were designed to limit downside risk and, as a result, tend to lag when the market is rising.

Mr. Kashkari, 39 years old, didn't specify which political office he is considering. But with no contests for U.S. Senate seats from California until Democratic Sen. Barbara Boxer's term expires in 2016, the next high-profile race in the state will be the governor's post. Gov. Jerry Brown, 74, a Democrat, hasn't said whether he plans to run again in 2014; a spokesman for the governor reiterated that Mr. Brown hasn't made any "pronouncements" on that.

A Republican would face an uphill battle for a statewide seat in California, where every statewide office is held by a Democrat and Republican registration has been shrinking as the state's population becomes younger and more ethnically diverse. In 2010, Meg Whitman, former chief executive of eBay Inc. (EBAY) and now chief executive of Hewlett-Packard Co. (HPQ), ran for governor as a Republican against Mr. Brown. She spent more than any gubernatorial candidate in state history and ended with only 41% of vote.

"I'm not the typical California Republican. I'm the son of immigrants," Mr. Kashkari said. "I come from modest upbringing. I have a successful track record. I'm an optimist. And I think something can be done if people work together."

He said he plans to seek advice from California Republicans and Democrats before making any decisions, but already has launched a campaign-style website at www.neelkashkari.com.

With his shaved head and cool demeanor under cross-examination at televised hearings, Mr. Kashkari became the public face of TARP, the $700 billion bank bailout launched during the George W. Bush presidency, and continued during the first several months of the Obama administration.

"Obviously TARP is very unpopular," Mr. Kashkari said. "But it's the best example we have in modern history of Democrats and Republicans coming together to do something controversial but absolutely necessary and absolutely successful. .. Both Sacramento and Washington, D.C., have a lot of politicians who want to do the easy things which'll make them popular. We're out of easy things to do."

A native of Akron, Ohio, Mr. Kashkari moved to California in 1997 as an aerospace engineer and later, after earning an MBA, worked there for Goldman Sachs. He moved to Washington to work at the Treasury in 2006 after Henry Paulson, who had been Goldman's co-chief executive, became Treasury secretary.

Pimco, based in Newport Beach, Calif., manages the world's largest bond fund, Pimco Total Return, which has assets of $285 billion.

The six funds Mr. Kashkari's 55-employee unit manages are Pimco EqS Pathfinder Fund, Pimco Eqs Emerging Markets Fund, Pimco Eqs Dividend Fund, Pimco Eqs Long/Short Fund, Pimco Emerging Multi Asset Fund and Pimco Dividend and Income Builder. Pimco's stock funds have been drawing new money, despite investors' shift away from actively managed stock funds. They had net inflows of $316.5 million in the U.S. in 2012, according to Morningstar.

-- Vauhini Vara contributed to this article.

Write to David Wessel and Kirsten Grind at david.wessel@wsj.com and kirsten.grind@wsj.com

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