Even though he won’t be in Michigan until Monday, former Vice President Joe Biden got a number of boosts to his campaign Sunday as surrogates hit churches, restaurants and union halls on his behalf.

Gov. Gretchen Whitmer, Lt. Gov. Garlin Gilchrist and Detroit Mayor Mike Duggan concentrated on Detroit to urge voters to either cast an absentee ballot or hit the polls on Tuesday for Biden. U.S. Sen. Tom Carper of Delaware and U.S. Rep. G.K. Butterfield of North Carolina went to the IBEW (International Brotherhood of Electrical Workers) union halls in Detroit and Monroe to help kick off door-to-door canvassing.

And U.S. Sen. Kamala Harris, a California Democrat and former presidential candidate, gave a key endorsement to Biden on Sunday morning and will join him for a campaign rally in Detroit on Monday.

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“There is no one better prepared than Joe to steer our nation through these turbulent times, and restore truth, honor and decency to the Oval Office," Harris said in her endorsement. "He is kind and endlessly caring, and he truly listens to the American people.”

The visits and endorsements came at a time when Biden is gaining momentum in the presidential primary after winning 10 of 14 states voting on Super Tuesday. On Saturday night, the campaign announced a $12 million investment in advertising in eight key battleground states, including Michigan.

On the Sunday before Tuesday’s presidential primary, politicians naturally hit the church circuit to reach some of the Democratic Party’s most dependable supporters — African Americans in Detroit.

“This is an important couple of days. The whole world is focusing on Michigan right now and with good reason,” Whitmer told the congregants at Citadel of Praise Church on Detroit’s west side. “When our back was against the wall and the auto industry was struggling, it was Barack Obama and Joe Biden who had Michigan's back. And it made our economy stronger. And so right now, in this moment, it's important that we have his back too.”

In 2009, the Obama administration shepherded through a federal bailout of General Motors and Chrysler, rescuing the struggling, Michigan-based automakers.

Later at the Good Times on the Avenue restaurant in Detroit, Whitmer met with diners and staff, asking one and all whether they had already voted, whether they knew that they could still vote by absentee ballot, and whether they realized they could even change their vote if they had already voted for a candidate no longer in the race. And she said that Biden would benefit from adopting the winning campaign strategy she used in 2018 of focusing on issues that really matter to voters like health care and fixing the roads, in order to defeat President Donald Trump in November.

“it's not any different than what we did in 2018. To be honest, it is about showing up. It is about staying focused on the dinner table issues that people care about,” she said. “And it's showing that you can get things done and that's why I was thrilled to jump in and throw my support behind Joe Biden.”

While Whitmer didn’t an endorse a candidate until after the Super Tuesday contests, she came on board on Thursday and became one of four national co-chairs of his campaign. Duggan has been a Biden supporter since the former vice president got in the race. He predicted that Biden will win, especially in Detroit.

“The reaction that I'm getting from Detroiters for Joe Biden is very strong,” he said. “So I will be very surprised if the vice president doesn't get strong support out of the city of Detroit."

And even though Biden doesn’t have a vast organization in Michigan, Duggan said he has history with the city and the state from his time as Obama’s vice president.

“When the auto industry was in bankruptcy, Joe Biden was here. In 2014, when Detroit was in bankruptcy, he was here every three or four months,” Duggan said. “People are making the decision for president not on whether somebody knocked on their door last week, but what they've seen from a very good man over many years.”

That’s the motivation for Joanne Barnes, of Auburn Hills, who retired from Chrysler in 2009, just as the automaker was getting a federal bailout.

“Biden is very personable. He acts human to me. He saved the day for all of us,” she said after having breakfast at Good Times. “I’m looking at him like the American Superman.”

But Brenda Thompson, a Detroit resident and supporter of U.S. Sen Elizabeth Warren’s presidential campaign, was leaning toward voting for Sanders.

She was leery of just casting a vote for Biden because he used to be the vice president.

“And then I heard Bernie last night and he really broke it down for me,” she said. “He really defined the issues for us and that resonated.

After three days of state and national campaign surrogates, Biden will be in Michigan Monday with a stop in Grand Rapids and a 7 p.m. rally in Detroit at Renaissance High School, 6565 Outer Drive West.

Contact Kathleen Gray: 313-223-4430, kgray99@freepress.com or on Twitter @michpoligal.