WASHINGTON (CBSNewYork/AP) — Support has been eroding for Democratic presidential hopeful Hillary Rodham Clinton, to the point where she has dropped below the 50-percent threshold.

As CBS2’s Dick Brennan reported, the drop came as emails from her private server were released.

Support has been growing for liberal Bernie Sanders (I-Vermont), and even for a potential presidential bid by Vice President Joe Biden.

In the latest poll of Iowa Caucus-goers, Clinton claimed 37 percent of support, just a seven-point lead over Sanders with 30 percent. Biden has 14 percent, even though he has not announced he is in the race.

“I don’t know if her campaign is in trouble, but our campaign is doing great,” Sanders said this past weekend.

Meanwhile Monday, the State Department released roughly 7,000 pages of Clinton’s emails — including about 150 emails that have been censored because they contain information that is now deemed classified.

Department officials said the redacted information was classified in preparation for the public release of the emails and not identified as classified at the time Clinton, a former New York U.S. senator, sent or received the messages. All the censored material in the latest group of emails is classified at the “confidential” level, not at higher “top secret” or compartmentalized levels, they said.

“It’s somewhere around 150 that have been subsequently upgraded” in classification, State Department spokesman Mark Toner told reporters.

Still, the increasing amounts of blacked-out information from Clinton’s email history as secretary of state will surely prompt additional questions about her handling of government secrets while in office and that of her most trusted advisers. The Democratic presidential front-runner now says her use of a home email server for government business was a mistake, and government inspectors have pointed to exchanges that never should have been sent via unsecured channels.

Toner insisted that nothing encountered in the agency’s review of Clinton’s documents “was marked classified.”

Government employees are instructed not to paraphrase or repeat in any form classified material in unsecured email.

Monday evening’s release amounts to more pages of email than disclosed in the previous three months combined. Once public, it will mean roughly a quarter of all of the correspondence Clinton qualified as “work emails” has been published.

Clinton provided the State Department some 30,000 pages of documents late last year, while deleting a similar amount from her server because she said they were personal in nature.

Meanwhile on the Republican side of the presidential campaign, Donald Trump’s so-called “Summer of Trump” dominance may be slipping ever so slightly. A new poll out Monday morning showed Trump is tied with Dr. Ben Carson in Iowa — each with 23 percent.

There have been hints of possible problems for Trump.

He led in a national survey from Quinnipiac University released last week. But when asked to describe candidates with one word, voters chose “arrogant,” “blow-hard” and “idiot” to describe Trump.

“Much like Hillary Clinton, he has, to use this word, lousy numbers as far as honesty; trustworthiness,” said Tim Malloy of Quinnipiac University. “Does he care about you?”

Trump spent the weekend hammering Clinton and her top aide, Huma Abedin – the wife of former U.S. Rep. and mayoral candidate Anthony Weiner.

“So Huma is getting classified secrets. She’s married to Anthony Weiner, who’s a perv. He is!” Trump told supporters. “Do you think there’s not a 5 percent chance that she’s telling Anthony Weiner now of a public relations firm what the hell is coming across?”

Clinton says she exchanged about 60,000 emails in her four years as secretary of state. She turned over all but what she said were personal emails late last year. The department has been making those public after scrubbing sensitive material.

The State Department advised employees not to use personal email accounts for work, but it wasn’t prohibited.

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