After the Women’s March in Washington and the demonstrations around the country, some have questioned whether those efforts could keep up steam, particularly given the wide range of issues being raised. In the months since the marches, smaller groups, known as “huddles,” have met around the country. Organizers said more than 5,600 such meetings had occurred, and pointed to the turnout at the weekend convention, as well as the number of potential female candidates, as more evidence that a sustained movement had emerged.

“For the folks that say, ‘O.K., you had this march and what’s going on with the energy?’: When I go out there, it’s everywhere,” said Stephanie Schriock, the president of Emily’s List, which helped sponsor the convention. Of the women voicing interest in running, she said, “We really see this as the next decade of candidates for office.”

Somewhat murkier, though, was precisely what would mark success — for the 2018 elections and for this meeting. Some here said the essential goal was seeing Democrats win control of Congress next year. Others said a main aim was that women turn out to vote in far larger numbers or that women win local and state races in unprecedented numbers, building a deep bench of future candidates for national slots.

“What I know is this: It will be tough to wake up the day after the 2018 election if we don’t have a good showing, maybe even harder than it was to wake up the day after the 2016 election,” said Alannah Boyle, 21, a student from New York City who rode nearly 12 hours with seven others to attend the Detroit convention. “We are doing so many small acts of resistance, and it’d be hard if there aren’t the results.”

The convention, held in the vast downtown Cobo Center and titled “Reclaiming Our Time” (a play on remarks by Ms. Waters at a House committee meeting), drew a wide range of women: old and young, and of different races, ethnicities, religious backgrounds and hometowns. Some people paid $295 to attend the conference, though many said they had been granted scholarships to come. The gathering included a lineup of female Democratic senators, but also local activists, would-be candidates and ordinary voters. Some men also attended, although Senator Bernie Sanders, who had been expected to speak, did not.

Before the weekend began, critics complained that Mr. Sanders, an independent from Vermont, ought not to be offered a high-profile speaking slot, given that it was a convention for and about women. The debate created a split among some here, creating tension during some events; panelists on one stage noted that some convention participants had threatened on social media not to come (or even to throw a separate convention) if Mr. Sanders appeared.