"We may look back on it and say those who are professional bettors saw a Democratic takeover coming and placed their bets accordingly," Mr. Ritsch said.
Indeed, various polls indicate the Democrats could win one or both houses of Congress in next month's elections. Public support of President Bush and of the war in Iraq is dropping, suggesting support for Republican leadership is weakening.
The securities industry is "rather bloodless in the way they give money," said Bruce Freed, co-director of the Center for Political Accountability, a Washington-based public interest group.
The Center for Responsive Politics data, which include contributions of at least $200 from political action committees and individuals associated with companies, isn't complete for the 2006 election cycle, which began Jan. 1, 2005. Still, an analysis of contributions during the first 18 months of that cycle clearly shows that securities firms are giving more money to Democrats.
The increase in Democratic contributions reflects the industry's desire to cozy up to a powerful Democratic senator: Sen. Hillary Rodham Clinton, D-N.Y.
Indeed, Ms. Clinton, who is viewed as a serious contender in the race for the White House in 2008, has been the biggest beneficiary of Wall Street's largesse, receiving $1.3 million. Ms. Clinton also received $320,000 in contributions from the banking industry, as well as $169,000 and $340,000 from the accounting and insurance industries, respectively.
"She's raised so much money, and she's from New York, which is the political piggy bank of the U.S.," Mr. Ritsch said.
Sen. Joe Lieberman, D-Conn., is the No. 2 beneficiary of contributions from the securities industry, receiving $788,000.
Sen. Rick Santorum, R-Pa., is No. 3, with $724,000.
Overall, the financial services sector has contributed more than $4 million to Ms. Clinton and $2.5 million to Mr. Santorum. Mr. Lieberman had received $2 million in contributions as of Sept. 11, according to the Center for Responsive Politics.
Another factor behind the securities industry's diminished support for Republicans could be the exit from Congress of House Majority Leader Tom DeLay, R-Texas, who resigned last year.
Mr. DeLay helped launch the K Street Project, a Republican effort to get Washington lobbyists to hire more Republicans and donate more. Without his leadership, "this year, you have a change in dynamics," Mr. Freed said.
Some Wall Street firms long have been in the Democratic camp in terms of the total amount of donations made by their employees. The Goldman Sachs Group Inc. of New York and its employees, for example, were the securities industry's top contributors to Democratic candidates as of Sept. 11, as they were in 2002.
So far in the 2006 election cycle, the company and its employees donated $2.6 million to political candidates and committees, 60% of which went to Democrats.