May increased partisanship lead to convergence of parties' policy platforms?

Parties face a trade-off between motivating partisans to participate in the election and appealing to issue-oriented middle-of-the-road voters. We show that, consequently, parties may diverge from the median voters' preferred policy by sending ambiguous messages to voters which include announcements of alternative platforms. Moreover, surprisingly, an increase in the size of a partisan constituency may lead to platform convergence towards the median voters' preferred policy. We identify two conditions for this outcome. First, the electorate is sufficiently divided such that full convergence does not occur and, second, the majority of the non-partisan voters is more inclined to the party with increased support of partisans.