President Barack Obama’s support among blue-collar whites has fallen below 30 percent, according to two new polls.

The unprecedented drop comes as Obama announced several controversial moves to bolster his support among minority groups, including his recent immigration reform and decision to come out in favor of same-sex marriage.

That immigration reform includes what critics say amounts to a de-facto amnesty for at least 800,000 illegal immigrants, many of whom may compete against blue-collar whites for jobs.

The action and reaction underlines the Democratic Party’s increased dependence on minority groups, unmarried women, government workers and whites with post-graduate degrees.

The Democrats’ electoral coalition will be highlighted June 12, when Vice President Joe Biden gives a speech to the NAACP’s annual convention in Houston Texas.

Biden is expected to launch a blistering attack on Gov Mitt Romney’s policies, similar to the speech he used at the recent convention organized by the Hispanic lobby La Raza. “There are voices among us who fear your inclusion,” Biden declared July 10, after depicting Republicans as “xenophobes.”

“There’s always been a fight between the voices of inclusion and the voices of exclusion. Between those pushing forward and those who continue to try to pull us back,” he told his La Raza audience.

The Obama campaign’s pitch to Latinos pitch has arguably been successful: Obama has the support of 66 percent of Latinos, compared to Romney’s support of 26 percent, according to a May poll by the Wall Street Journal.

Among African-Americans, Obama’s support has declined slightly, but remains at 87 percent, according to June poll by Gallup.

His support among the blue-collar whites has tanked, however.

A new Quinnipiac poll says Obama has support from 29 percent of white men who did not go to college. That’s down from 32 percent in April.

An ABC/Washington Post poll showed Obama’s support at 28 percent, a lurch down from 34 percent in May.

In 1984, Democratic presidential candidate Walter Mondale won 31 percent of white blue-collar workers, while being crushed by President Ronald Reagan’s landslide.

Reagan’s victory cracked the Democrats’ coalition that had existed since the 1930s, and began a gradual shift of blue-collar workers into the GOP coalition. That shift was temporarily reversed by President Bill Clinton, but has now accelerated under Obama’s progressive, Washington-centered policies.

The sudden drops in support comes amid record unemployment, debts and deficits, as well as Obama’s increased efforts to boost his support among minorities. A recent poll showed that Obama’s recent immigration measure, for example, was more likely to be opposed than supported by swing-voting white men in Ohio and Pennsylvania, both of which are swing states in the 2012 election.

To boost support among the gays and lesbians — who comprise roughly 4 percent of the voting-age population — Obama announced his support for a change in the meaning of marriage that would allow same-sex couples to get marriage licenses. That policy is unpopular among many blue-collar workers — white, Latino and African-American — who see marriage as a critical economic and social aid amid a stalled economy and swirling social changes.

The Democrats’ record low level of support among blue-collar whites, however, is offset by by that demographics declining share of the electorate.

Democratic partisans say they can win the election, despite such low numbers among blue-collar whites, if enough Latinos, Africa-Americans and white liberals come out to vote in November.

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