Regulators in charge of writing the Volcker Rule, which would ban banks from trading with their own money, were inundated with complaints and suggestions on Monday, the deadline to comment on a draft proposal. More than 200 letters were expected to be filed by the midnight deadline on the rule, which regulators outlined in October.

Commenters included the rule’s namesake, Paul A. Volcker, the former Federal Reserve chairman, who submitted a strongly worded defense of the rule’s intent in a letter on Monday. Others, like consumer advocates and lawmakers, criticized the draft rule for not being tough enough.

Senators Carl Levin of Michigan and Jeff Merkley of Oregon, both Democrats, led the effort to insert the Volcker Rule in the Dodd-Frank act, the sweeping regulatory overhaul passed in response to the financial crisis. In a comment letter on Monday, the senators said the proposed rule was “too tepid.”

But the loudest response came from critics like Wall Street trade groups and banks, who want to soften the rule. The rule, the critics said, is a threat to the health of the financial industry and the broader economy.

“This will make the overall economy less stable and less conducive to growth,” David Hirschmann, head of the Center for Capital Markets Competitiveness at the Chamber of Commerce, said in a letter.

The pushback against the Volcker Rule is the latest effort under way on Wall Street to mute the impact of Dodd-Frank. But the campaign against the Volcker Rule is more pronounced than banks’ earlier attempts to temper new regulations for lending and derivatives.

Wall Street firms, lawyers and trade groups churned out many Volcker Rule appeals. The Securities Industry and Financial Markets Association, or Sifma, hired the law firm Davis Polk to write multiple pitches to regulators.

A hodgepodge of Wall Street trade groups led by Sifma alone filed five comment letters on Monday, including one document that spanned 173 pages. A regulatory comment letter normally runs 10 to 20 pages. During the writing period, most big banks formed internal Volcker Rule “task forces,” often led by risk officers and lawyers, to coordinate the effort across trading desks and divisions, people briefed on the efforts said.