Story highlights Bernie Sanders' supporters are expected to get five out of 15 seats on the Democrat's convention platform committee

The agreement is unusual because DNC rules allow the chair of the party to pick members of the committee

Detroit (CNN) Bernie Sanders supporters will occupy a third of all seats on the Democratic Party's 2016 platform committee, the Democratic National Committee announced Monday, an agreement that will allow the Vermont senator to wield sizable influence on the party's platform this year.

Sanders and his supporters have complained for months that the Democratic Party was tilted against his insurgent bid and are worried that should he lose to Hillary Clinton -- as he is expected to do -- the issues that have animated his bid will not find a place at July's Democratic National Convention.

The agreement struck by both campaigns this month looks to ensure that doesn't happen. Sanders' five slots include several bold face names in progressive politics, including Rep. Keith Ellison of Minnesota and environmental activist Bill McKibben.

Clinton will appoint six members to the powerful platform committee, according to the agreement. Rep. Debbie Wasserman Schultz of Florida, the chairwoman of the Democratic Party, will name four members.

The agreement is unusual, in part because DNC rules allow the chair of the party to pick every member of the platform committee, a group that will hammer out, write and present the Democratic Party's platform at this year's convention.

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