LANSING, Mich. (AP) — Michigan Gov. Gretchen Whitmer is backing Joe Biden for president days before the state's Democratic primary, giving the former vice president another boost after his success on Super Tuesday.

Whitmer, who had not been planning to endorse a 2020 candidate, says Biden “has our backs.” She cites his work with President Barack Obama to add health coverage for millions of people and to rescue two of the Detroit Three automakers, General Motors and Chrysler, from financial ruin.

“He showed up for the people of Michigan when our health care and our auto industry were on the line,” the first-term governor said in a statement released Thursday to The Associated Press. “He helped us pick ourselves up and get back to work. I know he'll do the same as president.”

Of the six states voting next Tuesday, Michigan is the biggest prize in what has effectively become a two-man race between Biden and Vermont Sen. Bernie Sanders — with 125 pledged delegates at stake, the ninth-most overall. It also will be a crucial upper Midwest battleground in the fall.

“Joe Biden is the candidate we need to defeat Donald Trump in November,” Whitmer said a day after hinting that she might deliver an endorsement because “a lot of things have changed in the last 72 hours.” She said she decided to publicly support a candidate now because “we need our party to be united” to beat the Republican president.

Sanders narrowly won Michigan's primary over Hillary Clinton in an upset four years ago after drawing large crowds in college towns and elsewhere. He backed one of Whitmer's more liberal Democratic opponents in the 2018 gubernatorial primary but campaigned for Whitmer in the general election.

Sanders was set to rally supporters in Detroit and Grand Rapids on Friday and Sunday. Biden planned an event in Detroit on Monday, the eve of the primary.

Massachusetts Sen. Elizabeth Warren, who was assessing the path forward after finishing no higher than third in any Super Tuesday state, was scheduled to campaign in Lansing on Friday.

Whitmer will be the Biden campaign's fourth co-chair and serve as a top adviser and surrogate. Her profile grew nationally when she delivered the Democratic response to Trump's State of the Union address.

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