(Adds analyst comment, details, byline; updates shares)
By Jonathan Spicer
NEW YORK, July 31 (Reuters) - NYMEX Holdings Inc NMX.N reported sharply higher quarterly earnings on Thursday, beating Wall Street expectations, as the energy and metals exchange benefited from sizzling oil markets and a one-time gain from an investment in the Montreal Exchange.
The company, which is nearing a takeover by CME Group Inc (CME.O), also said it was satisfied with the direction debate was headed in Washington, where lawmakers have been weighing legislation that would curb speculation in energy markets.
"Continuing volatility in the energy markets" drove results, Chief Financial Officer Kenneth Shifrin said on a conference call with investors and media.
Second-quarter net income more than doubled to $94.3 million, or 99 cents a share, from $41.7 million, or 44 cents a share, a year earlier.
Excluding the $30.6 million one-time investment gain, as well as expenses from the pending merger with derivatives exchange CME, earnings were 83 cents per share. Analysts on average were expecting 81 cents, according to Reuters Estimates.
Revenue rose 29 percent to a record $210.8 million, above the $207.9 million Wall Street expected.
The investment gain was in cash and shares from Toronto Stock Exchange operator TMX Group (X.TO), which acquired the Montreal Exchange in May.
Richard Repetto, an analyst at Sandler O'Neill, said NYMEX's "solid results" reflect its investments and performance, as well as the volatility in energy markets.
Crude oil futures notched a series of record high prices in the quarter, helping to boost NYMEX's average daily volume by 30 percent. The exchange said volumes also benefited from investors grappling with volatile credit markets.
NYMEX shares were down 44 cents, or 0.5 percent, at $83.31. The shares have fallen about 37 percent this year, their value largely determined by CME stock activity and the likelihood of a successful cash-and-share buyout.
NYMEX and other exchanges have been lobbying U.S. lawmakers in recent weeks to kill proposed legislation that would tighten the position limits in energy futures contracts.
The bill, which was intended to curb the run-up in gasoline prices, failed in the U.S. House of Representatives on Wednesday.
"Certainly there were some extremist views taken and some very emotional views taken early in this debate," Chief Executive James Newsome said on the call. "We certainly think the cooler heads are starting to prevail."
The company said it is difficult to determine what effect the Congressional debate has had on volumes, and suggested any new legislation would have only a modest impact.
NYMEX's clearing and transaction fees jumped 31 percent to $180.4 million, while market data fees increased 15 percent to $26.9 million.
On the other side of the balance sheet, fixed operating expenses were up slightly at $42.9 million.
NYMEX, whose chief rival is IntercontinentalExchange Inc (ICE.N), set a dividend of 10 cents a share payable in September.
Earlier this month, CME sweetened its offer for NYMEX in an effort to win the support of at least 75 percent of the acquisition target's members. NYMEX management, which backs the takeover, said on Thursday it did not want to discuss it.
CME Chief Executive Craig Donohue told Reuters last week he expected job cuts if NYMEX members and shareholders vote to accept the deal, worth about $8 billion, on Aug. 18. (Reporting by Jonathan Spicer; Editing by Brian Moss and Maureen Bavdek)