In a swift blow to an initiative aimed at shaking up one of the stalwarts of the Harvard College curriculum, the Committee on Undergraduate Education in Economics voted down a proposal Tuesday for an alternative to the department’s introductory economics course.

Brought forth by Barker Professor of Economics Stephen A. Marglin ’59, the proposal suggested that the department offer students an alternative to the first semester of the popular Core, Social Analysis 10: “Introduction to Economics,” colloquially known as “Ec 10” and taught by Baker Professor of Economics Martin S. Feldstein.

The idea for the alternative course first appeared in a petition signed by over 700 students and alumni last month. The petition, circulated by the Students for Humane and Responsible Economics (SHARE), expressed frustration with what signers called the “conservative” slant of the class.

But the proposal has met with resistance, both from professors, who defend Feldstein’s course as sufficiently balanced, and from some students who signed a counter-petition arguing that the competing classes would segregate students along ideological lines.

The new course proposed to cover the same material as Ec 10 and to use the same basic textbook but would move at a slightly faster pace to allow time at the end of the course for critical analysis of the basic assumptions of economics, Marglin said.

But the committee, led by Maier Professor of Political Economy Benjamin M. Friedman, voted down the proposal Tuesday, saying that while the course was viable in itself, it was not an appropriate replacement for a semester of Ec 10.

“Members of the Committee unanimously thought that Professor Marglin should be encouraged to offer a version of this proposed course,” according to a statement issued by the department yesterday. “However, a clear majority of the Committee opposed having the course serve as a substitute for the first semester of Social Analysis 10.”

Committee member and Senior Lecturer on Economics Jeffrey Wolcowitz declined comment yesterday. No other committee members, including Friedman, could be reached for comment.

The proposal was first discussed in a preliminary meeting with committee members before spring break, which both Marglin and Feldstein attended. Responses were positive, according to Marglin.

“I was very surprised at the turnaround [at Tuesday’s meeting] because things looked so helpful at the first meeting,” Marglin said yesterday. “But the members clearly changed their minds.”

The proposal has one more shot to succeed, pending a vote by the full economics department scheduled for April 22.

But professors say that, in some ways, the decision is already made.

“The clear majority of the committee voted against this, and that will hold serious weight when the department votes [in two weeks],” Department of Economics Chair Oliver D. Hart said. “It’s unlikely that the proposed course will be able to serve as a substitute for Social Analysis 10.”

Students in SHARE, who met with Friedman about a month ago to discuss the proposal, said they were shocked at the outcome of Tuesday’s meeting.

“It’s completely outrageous that they rejected this after hundreds of students signed a petition,” said Daniel DiMaggio ’04, an active member of SHARE who took Ec 10 last year.