Rep. Joe Barton lost more than $154,000 on investments of his campaign funds during the last three months, according to a CQ MoneyLine study of campaign finance reports. The Texas Republican’s campaign fund losses are due in part to drops in energy company stocks, including BP.

Turbulence in the financial markets has taken its toll on several House campaigns, which lost in total more than a quarter of a million dollars in campaign funds since March because they invested in the stock market, but Barton’s losses make up the largest chunk of that.

Barton saw his bottom line fall in part because of losses in broad-based funds that invested in companies linked to the recent Gulf Coast oil spill. His campaign reported losing more than $13,000 in the Fidelity Select Energy Service, which lists Halliburton and Transocean Inc. among the fund’s largest four holdings. Transocean is down more than 36 percent for the year, while Halliburton is down nearly 6 percent so far in 2010.

Barton also lost more than $36,000 in Fidelity Dividend Growth, which bought just more than half a million shares of BP at the end of May — after the oil spill began — according to investment analysis service Morningstar.

Though Barton knew he was investing in energy-based stock funds, a spokesman for the Congressman said he was unaware of the individual stocks in which the fund was investing, including BP, Halliburton and Transocean.

“He was not aware of the new investment that they made” in BP, said Craig Murphy, a spokesman for Barton. “They did not notify him. They did not ask him. Obviously it is a well-known fund, and they just do what they want.”

Murphy added that it was not a conflict of interest for Barton to be the top Republican on the committee that controls energy legislation while investing in energy companies with his campaign contributions.

“There’s no conflict there,” he said. “He invests in lots of things, and it doesn’t impact his vote.”

Barton had other significant setbacks from individual nonenergy stocks, including drops of $37,800 in General Electric Co., $21,400 in Home Depot and $16,500 in the Lennar Corp.

Investing political contributions in the market is legal under current campaign laws.

House conflict-of-interest rules do not apply to campaign holdings, leaving Members free to invest their funds as they please.

Some of the biggest losses for the quarter were taken by campaign accounts of former lawmakers. For instance, the House campaign committee of former Rep. Joe Kennedy (D-Mass.), who served in Congress from 1987 to 1999, lost $71,000 because of “asset depreciation” in his Goldman Sachs account. The campaign account of former Rep. Chip Pickering (R-Miss.), who retired from Congress in 2009 to work on K Street, reported losing $27,000 with Fiserv Trust Co.

But not everyone lost money this quarter. Former Rep. Mark Foley (R-Fla.), who served in Congress from 1995 to 2006, made more than $29,000 on several individual stocks in his Fidelity account.