Democrats scrambled to regroup on Wednesday after a disappointing special election defeat in Georgia, with lawmakers, activists and labor leaders speaking out in public and private to demand a more forceful economic message heading into the 2018 elections.

Among Democrats in Washington, the setback in Georgia revived or deepened a host of existing grievances about the party, accentuating tensions between moderate lawmakers and liberal activists and prompting some Democrats to question the leadership and political strategy of Nancy Pelosi, the House minority leader.

A small group of Democrats who have been critical of Ms. Pelosi in the past again pressed her to step down on Wednesday. And in a private meeting of Democratic lawmakers, Representative Tony Cárdenas of California, Ms. Pelosi’s home state, suggested the party should have a more open conversation about her effect on its political fortunes.

But the most acute and widely expressed concerns were economic. Speaking after a meeting of the Democratic caucus on Wednesday morning, Representative Hakeem Jeffries of New York said the party was preparing to be “aggressively focused on job creation and economic growth.” And Representative Jim Himes of Connecticut, who represents an affluent district near New York City, said Democrats must do more to compete with what he described as expansive and unrealistic promises by President Trump.