A series of new polls show that swing voters and Democrats are souring on President Barack Obama.

The drop-off is strong enough to weaken the president’s clout during the next several months of debates, demonstrations, donations and disputes over hot-button issues, such as immigration and guns, the deficit and taxes.

This week, Obama is giving a series of speeches about the economy, which his supporters hope will shift media and public attention away from issues that hurt his support — the economy, scandals, unemployment — and back to politically popular fights with Congress.

A Marist Poll conducted for the McClatchy news chain showed that Obama’s job approval fell from 50 percent in April to 41 percent in the first week of July. His rating on the economy shrank to 37 percent approval, 56 percent disapproval, suggesting that even some in his base are turning negative, said the poll, released July 23.

His support among independent voters, his support is down 17 points since April to 30 percent, and disapproval is at 59 percent, said the poll.

A similar drop is also visible in California, where a July 22 Field Poll showed that his approval has plunged from 62 percent in February, to 52 percent in July.

The greatest losses were among partisan Democrats, younger voters and women, said Mark DiCamillo, director of the Field Poll. His support among women fell from 68 percent to 53 percent, and his support among voters younger than 39 fell from 71 percent to 57 percent.

A Washington Post/ABC poll of 1,002 adults showed that Obama support has slipped below 50 percent.

That poll also showed only 42 percent support for Obamacare, and that only 46 percent for a rewrite of the nation’s immigration laws.

Worse, only 19 percent of respondents strongly support the controversial Senate bill, while 30 percent oppose it strongly.

The poll showed that 40 percent of respondents would be “relieved” if the bill fails, while only 13 percent percent say they would be angry at the failure.

Obama has been pushing for the Senate bill, which would add 46 million immigrants — most of whom likely will vote Democratic — over the net 20 years. “We will not let up in the push for immigration reform — it is huge priority for the president,” White House spokesman Jay Carney said Tuesday.

So far, despite much political aid from business and the media, Obama hasn’t managed to persuade a majority to support the bill, said the poll, released July 23.

The bulk of the opposition comes from GOP voters, who worry the bill would hurt U.S. workers and the GOP’s future chances with those workers.

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