“I want to urge you to join us, instead of fighting us in this effort,” Mr. Obama said in his address at Cooper Union in Manhattan. “I’m here because I believe that these reforms are, in the end, not only in the best interest of our country, but in the best interest of the financial sector.”

Image President Obama talked of Wall Street’s “reckless practices” in his address to the top bankers on Thursday in New York. Credit... Doug Mills/The New York Times

The regulation battle has become the president’s top legislative priority since he signed his health care program into law last month, and both parties are jockeying for position six months before midterm elections. Mr. Obama and his allies have eagerly portrayed Republicans as handmaidens of Wall Street while Republicans have accused Democrats of trying to strangle the market and institutionalize bailouts.

While Mr. Obama avoided directly criticizing Republicans in his address, the partisan tension in the capital heated up again when Senate Republicans blocked an effort by Democrats to start debate on their regulation bill. Senator Mitch McConnell of Kentucky, the Republican leader, said Democrats were pre-empting negotiations, while Senator Harry M. Reid of Nevada, the Democratic leader, said Republicans were simply stalling.

Business interests and their allies used Mr. Obama’s visit to New York to trumpet their opposition to his plans. The New York Post ran a front-page editorial under the banner headline, “Dear Mr. President, Don’t Kill the Golden Goose: City Economy Imperiled in the Name of ‘Reform.’ ” The United States Chamber of Commerce took out full-page ads in New York newspapers echoing the concerns of Mayor Michael R. Bloomberg, saying that “beating up on Wall Street may be good short-term politics — but not if it gets in the way of the right solutions.”

Republicans argued that Mr. Obama’s plan would encourage risky behavior and empower regulators who failed to use the authority they already have. “President Obama says he believes in the power of free markets but his policies prove otherwise,” said Representative Spencer Bachus of Alabama, the senior Republican on the House Financial Services Committee. “Under the Democrat plan, certain financial institutions have no freedom to fail, and are instead propped up by taxpayer bailouts and government loan guarantees.”