Joe Biden picked up a major endorsement in Michigan from the state's governor, Gretchen Whitmer. Biden is quickly consolidating support from centrist Democrats as the race narrows between him and Sanders.

Whitmer told MSNBC's Morning Joe that she would be voting for Biden in the state's March 10 primary.

Six states hold primaries next Tuesday, but Michigan has the most delegates, with 125 up for grabs.

Sanders won Michigan in 2016's Democratic primary but President Donald Trump claimed the state in a surprise victory that November. Democrats have hoped to reclaim it in 2020.

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Michigan Governor Gretchen Whitmer endorsed Joe Biden for president on Thursday ahead of the state's critical March 10 primary.

"As we go into Michigan's election on Tuesay, I am going to be voting for Joe Biden," Whitmer, a Democrat, said in a Thursday morning appearaince on MSNBC's Morning Joe.

On Wednesdsay, former Michigan Governor Jennifer Granholm, who served from 2003-2011 ,also endorsed Biden.

Michigan is the biggest prize out of the six states that hold primaries on March 10, with 125 delegates. Sanders won the 2016 Democratic primary there, beating Clinton by more than 18,000 votes. But the state is also a Democratic target for the general election this fall, after Donald Trump surprisingly won Michigan in 2016.

In recent days, former Obama officials such as U.N. Ambassador Samantha Power and Defense Secretary Chuck Hagel, and former presidential candidates like Minnesota Senator Amy Klobuchar, have lined up behind Biden as the race narrows between him and Sanders.

"Joe Biden is someone that I know, is working to protect healthcare that was expanded under the Obama administration," Whitmer said, before telling a personal story about her mother's battle with brain cancer.

Whitmer was elected governor in 2018, after defeating Sanders-backed progressive Abdul El-Sayed in the state's Democratic primary. El-Sayed, in turn, has endorsed Sanders for president in this election cycle.

"Every time, whether it comes to health care, whether it comes to housing, whether it comes to a job that pays a living wage, Bernie Sanders is the answer," El-Sayed said in a video for the Sanders campaign announcing his endorsement.

Sanders is currently polling ahead of Biden in Michigan, according to a FiveThirtyEight polling average of the state. As of March 3 — Super Tuesday — Sanders was polling at an average of 30% support, while Biden received an average of 20%. However, the average does not include any polling taken after Super Tueday, when Biden staged a surprise comeback to win 10 of the 14 states up for grabs. Sanders won Vermont, Utah, and Colorado, and is projected to win California, which is still counting its ballots.

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