West Virginia senator Joe Manchin has emerged as one of the biggest stumbling blocks to the passing of Joe Biden’s ambitious domestic agenda, declaring he will vote against a key voting rights bill and also blocking reform of the filibuster – a rule that at the moment allows Republicans to kill Democrat legislation.

Yet Manchin is no Republican. He is a key member of Biden’s party, and in a 50-50 Senate his vote is the lynchpin of political power and crucial for passing Biden’s plans. Yet Manchin is seen by many Democrats as sabotaging his own president’s efforts to be a transformational leader who can help the US recover from the pandemic in the same way Roosevelt helped America recover from the Great Depression.

To many people outside West Virginia, Manchin’s behavior is a mystery: how does someone take such a stand against their own side? But for many West Virginian Democrats Manchin’s tactics and those of his state West Virginia Democratic party leadership are no surprise at all.

In fact, examining West Virginia’s Democratic politics shows that Manchin’s undermining of Biden’s efforts, especially around voting rights, should have been entirely expected.

Manchin’s opposition to the For the People Act, a bill that aims to expand voting rights and reduce the influence of money in US elections, has angered Black Americans across the country. But earlier this year, West Virginia’s all-white Democratic party leaders submitted a draft affirmative action plan to the national party without input or approval from a newly formed affirmative action committee, a group whose membership includes women, people of color and people with disabilities.