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Both strategies were shown to support voters in voting for their preferred candidates.
Campaigns Against Vote-Selling in the Philippines: Do Promises Work?
Vote-buying and vote-selling obstruct the democratic process, yet they are still common in many developing democracies. In the Philippines, researchers asked voters to make a promise: either not to take money from politicians or, if they did, to still vote according to their conscience. Researchers found that the promise significantly reduced vote-selling, cutting the number of people who sold their votes by 11 percentage points in the smallest-stake elections. These results suggest that asking voters to pledge not to sell votes can help reduce vote-selling in elections where the stakes are lower.
Reducing the Incidence of Vote-Buying in Uganda
In Uganda’s 2016 elections, researchers evaluated a large anti-vote-buying campaign that focused on dissuading voters from selling their votes and having villages make collective declarations to refuse offers of gifts or money in exchange for votes. They found that the campaign did not stop voters from accepting gifts on all sides. However, voters were more likely to vote for their preferred candidate. Vote shares also decreased for incumbents while they increased for challenger candidates—who were less financed—although this effect faded by the 2021 elections.
Other research on vote-buying and selling, from J-PAL, shows that radio ads are an effective strategy to educate and mobilize voters and anti-vote-buying radio campaigns can decrease vote shares for vote-buying candidates.