Both candidates used their visits to pledge more federal funding to the country’s ailing public housing system, where more than one million people — approximately a third of them in New York City — reside. This is a promise whose execution would, of course, rely on a compliant Congress. In terms of immediate impact, though, the visits demonstrated the power of attention to beget engagement. In all three of the housing complexes visited by the two candidates, voter turnout rates increased significantly over those recorded during the 2008 presidential primary, even though residents then had the chance to cast a vote for the candidate who would be the first black president. Of the 466 registered Democrats living in the Howard Houses, 112 voted on Tuesday — a lower turnout rate than the one for Democrats citywide, which was 37 percent, but an increase over the 2008 figures, when only 81 voted. (These figures, calculated by the political consultancy Prime New York, also show Hillary Clinton having won all three housing developments.)

Even Franklin Delano Roosevelt, under whose administration the federal public housing system was born, had a certain hesitation about getting too close. It wasn’t until 1937, when liberals in New York pushed his administration to build by organizing mass rallies and housing exhibitions (as Mr. Bloom recounts in his book “Public Housing That Worked: New York in the Twentieth Century”), that the president finally acquiesced, having believed all along that Americans should own their own homes, “however modest,” as he put it. As early as 1963, Gov. Nelson A. Rockefeller, a committed urbanist who held on to utopian ideas about renewal, began to back away from the idea of housing subsidies, saying in a speech to the New York State Women’s Legislative Forum that he was trying to get taxpayer money out of housing, and private capital into it, to create “an irrigation system, as you do getting water to an arid area.”

No matter what sort of fiscal innovations public housing officials conceive, the government spigot needs, in effect, to run. Now, at least, the conversation has been revived.