J.P. Morgan Chase & Co. (JPM) turned up as an adviser on deal after deal this month, lifting it to the No. 1 U.S. mergers and acquisitions ranking this year from No. 6 just a year ago.

The jump is a dramatic one for the New York-based bank, which has tried for years to catch up to rivals like Goldman Sachs (GS) in the annual M&A bragging rights contests.

Without the credit for advising on its own $58 billion acquisition of Bank One earlier this year, J.P. Morgan had $233 billion in deals this year, more than double a year earlier. That would have put it in the fourth spot, according to market research firm Dealogic (search).

The next issue, some analysts say, is holding onto a top spot in M&A after fighting for years to rise up the ranks. Once known as the banker for oil and railroad magnates, J.P. Morgan is now the nation's second-largest bank.

Its agreement to combine with Chase Manhattan in 2000 was aimed at gaining the size to compete with both Goldman and Citigroup, the banking industry leader. And as Chief Executive William Harrison built its vast commercial banking businesses, he was able to use them to expand J.P. Morgan's investment banking division.

That's a game that Chief Operating Officer Jamie Dimon (search), who is expected to become CEO in 2006, knows well from his days at Citigroup, long one of the top M&A advisory firms, ranking fourth this year and third last year.

"This is a core business that Jamie Dimon wants to expand," said analyst Richard Bove of Punk Ziegel & Co. "If you look at the business, there are six or seven that he is not interested in. This is definitely one where he will put capital."

In 2003, J.P. Morgan advised on $98.3 billion worth of deals in the United States, compared with $246.8 billion for Goldman Sachs. But this year, J.P. Morgan's $291.2 billion in U.S.-related deals beat Goldman Sachs' $289.6 billion, according to data provided by research firm Dealogic.

J.P. Morgan secured its place with the help of a slew of deals during the past few weeks. The company had a piece of the advisory business for Sprint Corp's $36 billion agreement to buy mobile phone company Nextel Communications Inc. and Johnson & Johnson's $24.5 billion bid for medical device maker Guidant Corp.

J.P. Morgan also advised on this week's $13 billion offer by nuclear power company Exelon Corp. for New Jersey utility Public Service Enterprise Group Inc.

The bank's 2004 gains reflect several years of consistency in the mergers and acquisitions business, according to Doug Braunstein, head of investment banking coverage.

"One of the big things we've done is we've maintained a distinct M&A practice when a number of competitors dissolved that business and then reinstated it," Braunstein said. "There aren't a lot of new names and faces. That allows you to develop relationships and builds trust."

The company has 1,500 investment bankers, of which 200 specialize in M&A, in areas including Europe, China and India.

The value of U.S. mergers involving private equity firms and other financial sponsors more than doubled to $126 billion industrywide this year, accounting for 15 percent of the nation's total deal volume. But recent transactions have involved acquisitions of telecommunications, energy and technology companies by their competitors.

J.P. Morgan has done well as M&A has picked up because it is not particularly focused on one industry, Braunstein said, but instead aims at many.

"The resurgence in (M&A) activity is from as broad a base of industries as it has been in a long time," he said.

But one analyst said the increased presence of financial sponsors in the M&A market in 2004 played to J.P. Morgan's strength in financing and loan syndication, and the company may find it difficult to hold onto market share when corporations assume a greater role again.

"They have really increased their M&A market share among financial sponsors," said Brad Hintz of Sanford C. Bernstein. "The jury is still out whether they've increased with the corporations."

Goldman Sachs, Citigroup, Morgan Stanley, Merrill Lynch and other competitors that typically dominate M&A rankings are not going to cede this ground easily, he said.

"It will be a slow and difficult fight to wrest market share away from the leaders," Hintz said.

A J.P. Morgan spokesman said that many of the largest deals the company did in 2004 were in fact strategic. Besides Nextel, Guidant and Exelon, the company advised Santander Central Hispano on its purchase of Abbey National and the Sony consortium on its purchase of Metro-Goldwyn-Mayer Inc.

In 2003, the company advised on Vivendi Universal Entertainment's merger with NBC, Olivetti's purchase of Telecom Italia, and Merck & Co. Inc. on its spinoff of Medco Health Solutions Inc.