Lorenzo Meyer, a politics professor and author, joined the volunteer forces of 1985, and is proud that his grown-up children took to the streets this week. He described the stark differences between the two experiences. “Back then, we took almost two days to get to the buildings,” he said. “It was very hard to find information on what was happening. This time, there were text messages and social media feeds telling people where to go. And now the social energy is so strong it’s impossible to repress.”

The brigades of 1985 had an impact on Mexican politics, Dr. Meyer said. Angry with a government they saw as uncaring, these empowered volunteers sought change. Many became activists fighting to end the hegemonic rule of the Institutional Revolutionary Party, or P.R.I. The capital became a bastion of opposition, and the P.R.I. lost political control of it in 1997, before losing the presidency in 2000, after seven decades.

The latest mass mobilization may also have a lasting political effect. The country now has multiparty democracy, and more open media and civil society. But people are angry about officials embezzling millions of dollars, governors working with drug traffickers and brutal violence that haunts communities. The P.R.I. returned to power in 2012 under President Enrique Peña Nieto, but he has suffered his own corruption scandals and his approval ratings have at times dropped to the teens.

A certain political reaction to the earthquake is already erupting. As it became clear that thousands had lost their homes from the tremor, people started online petitions calling for Mexico’s electoral institute to redirect hefty campaign finances for a presidential vote next year to earthquake relief. One of these petitions rapidly topped a million signatures.

A group created to support the petitions, FuerzaMexico, emphasizes the links between the political movements of past and present. “After the earthquake of 1985, Mexican civil society showed a power of solidarity and union without precedent; now we need it again,” it says on its page on the Change.org petition website.

A heightened awareness of people power could favor the presidential hopeful Andrés Manuel López Obrador, who trumpets a populist anti-establishment discourse from the left. A former Mexico City mayor, he already leads many opinion polls for the 2018 election as he calls for “el pueblo” to defeat a “mafia of power.” However, the advantage could swing to an independent candidate who offers an alternative to politicians and appeals to the many young professionals in the ranks of the volunteer brigades. Various personalities, including a TV anchor, an academic and a human rights defender, have expressed interest in running.

It could also strengthen Mexico’s resolve against the aggressive stance of the Trump administration, Dr. Meyer said. Around the rubble, the armies of volunteers often raise their fists and shout in unison, “Viva México.” “When we shout this, there is an implication that we are standing up to the hostile policies of the United States,” Dr. Meyer said. “After all of the recent insults, the humiliations, it is a way of reaffirming our pride.”