On 20 and 21 January 2018, hundreds of progressive groups organized another Women’s March. In the United States alone, between 1,856,683 and 2,637,214 people in at least 407 locations marched, held rallies and protested. There were marches in all 50 states and the District of Columbia, including in 38 state capitals. Although the number of participants declined from the massive march in 2017, this is a very significant show of strength.

Progressive movements are not the only ones that have turned to mass mobilization to build power from below. Donald Trump himself came to power on the heels of a rightwing populist movement that had its origins in the Tea Party protests of 2009.



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Several years ago, several Harvard professors published a paper on the effects of Tea Party protests on electoral and political outcomes in the 2010 midterm elections. They found that higher levels of participation translated into increased Republican voter turnout, Tea Party electoral victories, increased membership in Tea Party committees and organizations, and – ultimately – changed voting behavior among elected officials who wanted to appease Tea Party protesters.

Why is this relevant for understanding the Women’s Marches? If it is true that participation in mass protests has impacts on all sorts of electoral outcomes, then the Women’s March has unprecedented potential to alter the political scene, for three core reasons.

First, the sheer size of the Women’s March is impressive. The Tea Party had its largest day of single-day demonstrations on 15 April 2009, where between 440,000 and 810,000 participants turned out in 542 rallies nationwide, with a mean attendance of 815 people per protest.



In contrast, in the Women’s March of 2017, we estimated between 3.2m and 5.2 million marchers across 654 events. Our low estimate shows mean attendance per event of 5,178. Our high estimate shows mean attendance per event of 6,886. This showing is about six to seven times larger than attendance at the Tea Party rallies of 2009.

This is important, because according to Madestam and co-authors, the number of participants in each Tea Party event significantly impacted the voting behavior of the Republican representatives in their districts to reflect Tea Party goals. The more participants, the greater the effect. If these effects hold the same potential for progressive movements and leftist politicians, then we should expect impressive political impacts at the polls.

Second, participation in the first two Women’s Marches has been much more durable than in the first two years of the Tea Party rallies. The opening salvo of a protest cycle can often be large and dramatic, fizzling out over time as protest fatigue sets in. This certainly seemed to happen with the Tea Party. Much of the excitement and energy visible in the 2009 rallies was much more subdued in the following years.



Most people who associated with the Tea Party became involved in formal organizations, which began to focus more on winning elections rather than mass mobilization. By 2010, average participation in 2010 Tax Day demonstrations reportedly dropped by over two-thirds.

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But in 2018, the decline in Women’s March participation was more modest in both absolute and relative terms. We tallied 407 Women’s March demonstrations in the US, with average attendance between 4,848 and 8,315 per event. In other words, although last weekend’s mobilizations were half the size of the Women’s Marches of 2017, they were still six to 10 times larger than the largest Tea Party protests on Tax Day in 2009. This suggests a certain durability and commitment among Women’s March participants that may indicate more dramatic political outcomes.

Third, the Women’s Marches have been part of a much broader, persistent, and enduring resistance to Donald Trump and his policies in the United States. Far from existing in isolation, the Women’s Marches seem to provide an opportunity for many different progressive groups to come together in collective action – an important step in broadening participation and coalition-building. Although such efforts always come with their own tensions, successfully navigating them creates opportunities for expanding and leveraging political power in the streets as well as at the ballot box.



Women’s March organizers and participants certainly seem to be thinking along these lines. The March’s intent in 2018 was “Power to the Polls” – street protests tied to concrete political action, like registering to vote or running for office.

Indeed, the early electoral signals have suggested that the anti-Trump movement is having success. Democrats are winning or closing gaps in special elections, with much attention to the results for the Alabama Senate seat and the Virginia legislature.

We should not overplay these limited electoral results, but neither should we ignore them. A year of protests can be translated into hard political power. Far from indicating a slowdown, the 2018 march showed the continuing potential of the Women’s March to spur a major political mobilization.