Democratic presidential candidate Barack Obama, campaigning in a state that poses several problems for him in the fall, toured a Chrysler stamping plant before pledging to pump an extra $200 million a year into efforts to revitalize the nation's manufacturing sector.

One day after blue-collar workers overwhelmingly rejected him in West Virginia's presidential primary, Obama came to this auto-making suburb of Detroit to announce plans to create an "advanced manufacturing fund" to promote industries likely to keep jobs in the United States rather than see them move overseas.

The attention the Obama campaign is paying to general election states - Missouri on Tuesday and Michigan today - are signals that West Virginia is seen as a blip on his campaign radar, reports CBS News correspondent Dean Reynolds.

Obama also stepped up his criticisms of Republican presidential candidate John McCain, saying the Arizona senator offered no solutions when he told Michigan voters in January that many of their lost jobs would not come back.

McCain "was right" about that, Obama said in remarks prepared for a midday speech. "But where he's wrong is in suggesting that there's nothing we can do to replace those jobs or create new ones."

He proposed spending $90 million a year to double the Manufacturing Extension Partnership. The program has helped manufacturers improve efficiency and growth, Obama said, but has been underfunded. Another $100 million annually would launch the advanced manufacturing fund, which would award grants to businesses working with researchers to develop and expand products and efficient practices.

The Illinois senator spoke to union workers and their families at Macomb County Community College in Warren, Mich., after touring a Chrysler plant in Sterling Heights. The region is rich in so-called Reagan Democrats, who have often abandoned the party when it nominates candidates they view as too socially liberal, but who also have rejected Republicans they see as insufficiently concerned about working-class families living from paycheck to paycheck. 

Wearing a suit, safety goggles, earplugs and a flag pin, Obama entered the Sterling Stamping Plant and shook hands with factory workers.  

A pool reporter from Politico.com wrote: The reception was typical of those he receives elsewhere: Chants of “Obama,” lots of picture snapping, a sense of orderliness that eventually descends into semi-controlled chaos.

After he shook hands, Obama walked to several assembly lines, stopping every few feet to shake more hands. He watched metal parts tumble off conveyer belts. 

He was guided by Dean Hendrickson, the plant manager, and Bob Stuglin, president of UAW 1264. His conversations could not be heard by the press because the factory floor was very noisy.

Karen Palms, 44, a quality inspector from Detroit, said Obama had some work to do in Michigan and at the plant.

“He may do better by him coming down here and talking to people on the plant floor,” said Palms, who described herself as a Democrat who favors Obama – at this point – because he holds a lead in the delegate count and popular vote.

“He has work to do,” she said. “This will help a whole lot because he is here with the people working in the auto industry.”

On at least one occasion, Obama got too close to several sharp pieces of metal and had to be told to move away by Ken Gross, a health and safety representative for the United Auto Workers.

"Whoa, senator, that is really sharp,” Gross said as Obama stepped back from the pieces of metal – a body side for a Sebring.

Obama smiled and instead reached out to shake Gross’s hand, possibly unaware of Gross’s warning. 

Gross looked pleased: “I just saved the senator from being cut and me doing a lot of paperwork.” 

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Strategists see Michigan as a must-win state for Obama. Democratic presidential nominees have carried it in recent elections, but by narrow margins, and McCain has campaigned here several times.

A scheduling quarrel caused the national Democratic Party to essentially nullify Michigan's Jan. 15 primary, and Obama neither campaigned in the state nor had his name on the ballot. Now, within reach of securing the nomination despite Sen. Hillary Rodham Clinton's big win in West Virginia, Obama is trying to make up for lost time. He also hopes to soothe the anger and confusion that many Michigan Democrats feel over the intraparty fracas, which has yet to resolve how the state's delegates will be seated at the August Democratic convention.

In a bright spot for Obama, he picked up three more superdelegates after the West Virginia loss, offering fresh recognition from Democratic leaders of his inevitable nomination.

His campaign announced the support of Rep. Peter Visclosky of Indiana and Democrats Abroad chair Christine Schon Marques, who will get only a half vote at the national convention because the Democrats Abroad send double their allotted superdelegates and give them each a half vote.

A third superdelegate, College Democrats vice president and University of Wisconsin-Madison student Awais Khaleel, also announced Obama is his choice in video posted on YouTube.

Clinton also picked up a superdelegate, Tennessee Federation of Democratic Women Vicky Harwell, her campaign said.

An embattled Clinton is urging party leaders to take a hard look at West Virginia, which she won with 67 percent of the vote. But her victory did little if anything to knock Obama off stride as he approaches the 2,025 delegates needed to give him the presidential nomination.

"While Clinton’s decisive West Virginia win doesn’t change the overall direction of a race that is lurching toward an end, it won’t help Obama in his transition to a general election campaign," said CBSNews.com senior political editor Vaughn Ververs. "And there are continuing signs which, if not a threat to his ability to win the nomination, can’t be comforting for him or his party." 

(Click here to read Ververs' full analysis).

Including delegates won in West Virginia and new superdelegates, Obama has 1881 delegates to Clinton's 1711. (Click here for the full CBS News state-by-state tally.)