Sidney Blumenthal, a longtime Hillary Clinton friend who was an unofficial adviser while she was secretary of state, taking a lunch break from being deposed in private session of the House Select Committee on Benghazi at the US Capitol on June 16. REUTERS/Jonathan Ernst A new batch of messages from Hillary Clinton's private email account that was released on Monday evening shows she received advice about political strategy from her controversial confidant Sidney Blumenthal in the lead-up to the 2010 midterm elections. Blumenthal's suggestions focused on attacking Rep. John Boehner (R-Ohio).

Boehner became speaker of the House of Representatives after the GOP's spate of victories in the 2010 race. In the weeks surrounding the election Blumenthal sent multiple messages to Clinton about Boehner. Among other things, Blumenthal called Boehner an "old scandal ridden hack Republican" and described him as "louche, alcoholic, lazy, and without any commitment to any principle."

The messages were part of the fourth batch of emails from Clinton's private account that was released by the State Department on Monday. In May, a federal judge ordered the agency to release Clinton's emails from her time as secretary of state on a rolling basis at the end of each month. Clinton's use of a private email address for official business while she led the State Department from 2009 through 2013 has led to an ongoing scandal as she embarks on her presidential campaign. Critics argue that Clinton's private email server may have violated regulations and compromised sensitive information. Clinton and her team have steadfastly maintained her email practices were safe and in compliance with all rules and regulations.

A representative for Boehner's office released a statement in response to Blumenthal's comments that credited the House speaker with exposing problems with Clinton's "mishandling of classified information."

"The fact is the only reason that the mishandling of classified information by Hillary Clinton and her staff has been exposed is because of Speaker Boehner's decision to create the select committee and our members' diligence and hard work," the statement said.

In May, Boehner established a select committee dedicated to investigating the 2012 terrorist attacks on the US diplomatic compound in Benghazi, Libya. Clinton has been criticized for her handling of the incident, and the GOP-led committee has called her to testify about her use of a private email server.

Emails from previous State Department releases of Clinton's correspondence show Blumenthal advised Clinton on an extensive array of foreign-policy issues. Among other things, Blumenthal provided Clinton with unofficial intelligence about the situation in Libya. Blumenthal's communications with Clinton about Libya have caused controversy, though she has maintained his advice was unsolicited.

The new emails show Blumenthal sent Clinton lengthy memos ahead of the November 2010 elections and the majority of this correspondence targeted Boehner. Blumenthal did not respond to a request for comment on this story.

Democratic presidential candidate and former U.S. Secretary of State Hillary Clinton speaks to guests gathered for a campaign event on the campus of Des Moines Area Community College on August 26, 2015 in Ankeny, Iowa. Carlos Barria/Pool photo via AP Clinton's replies indicate she read Blumenthal's messages and that she was communicating with others who were attempting to influence the Democratic Party's strategy for the 2010 campaign.

In a message dated September 1, 2010, Blumenthal forwarded Clinton a Huffington Post article written by political analyst Drew Westen that contained suggestions for how Democrats should approach the election. Blumenthal's subject line for that message described it as "more on mid-term strategy."

"I'll write you another memo very soon," he wrote.

Blumenthal clearly believed it was imperative that Democrats focus on Boehner. On September 3, 2010, he sent Clinton an article about an USA Today/Gallup poll that he said "underscores need to elevate Boehner." Blumenthal included a note counting down the days to the election and suggested it was urgent for Democrats to adopt his Boehner-centric plan of attack.

"58 days left," Blumenthal wrote. "Whether the Democrats have the ability and will to execute is a separate subject: 'If it were done, when 'tis done, then 'twere well it were done quickly...' Making Boehner the GOP poster child should be systematic and relentless. Tick, tock, another day gone."

Three days later, on September 6, Blumenthal sent Clinton a lengthy strategy memo that he indicated was the third one he crafted for her on the 2010 election. The memo included intelligence Blumenthal claimed he gathered from pollsters and other sources. Blumenthal argued it was clear installing Boehner as the speaker was the GOP's "stealth agenda" for the midterm races.

"Everything, but everything, is about making John Boehner, that old scandal ridden hack Republican, the Speaker," Blumenthal wrote. "No matter what the Republicans say, the ultimate issue is the Boehner power-grab."

Clinton forwarded this memo to an aide, Lauren Jiloty, and requested a copy.

"Can you print the memo w/out any identifiers?" Clinton asked.

On September 8, 2010, Blumenthal forwarded Clinton an excerpt of another poll that he said provided "more evidence on why focusing on Boehner is important."

Three days later, he sent Clinton a New York Times article that highlighted Boehner's connections with lobbyists. Blumenthal seemingly begged Clinton to get Democrats to launch a television blitz based on Boehner's lobbying ties.

"Paid TV ads, please," he wrote.

Blumenthal is a former writer and senior adviser to Clinton's husband, President Bill Clinton. In addition to his work in her husband's administration, Blumenthal also advised Clinton's failed 2008 presidential campaign. In 2009, Clinton unsuccessfully pushed to get Blumenthal a position at the State Department. That same year, Blumenthal became a full-time employee of the Clinton family's charity foundation and was reportedly paid $10,000 a month. During this time he also received money from the liberal watchdog group Media Matters and the progressive Super PAC American Bridge.

House Speaker John Boehner (R). Jonathan Ernst/Reuters On October 6, 2010, Blumenthal sent Clinton a Media Matters memo written by Westen that called for liberals to push a series of poll-tested "narratives" that would "put Boehner front and center."

Westen wrote that research indicated "progressives should not only talk about Boehner but define him and his agenda."

Blumenthal's message to Clinton suggested he worked on the polling.

"Got this poll done with Brock; Begala helped," Blumenthal wrote.

This was almost certainly a reference to David Brock, who founded both Media Matters and American Bridge, and Democratic political consultant Paul Begala.

On October 8, 2010, Blumenthal forwarded Clinton another Huffington Post article by Westen that highlighted Media Matters' polling on Boehner. This time, Clinton replied.

"Are you reachable by phone tonight?" she asked.

Blumenthal responded with his availability. The next day, he sent along an article about a House candidate who participated in World War II reenactments in a Nazi uniform. Blumenthal suggested this could be ammunition for another attack on Boehner.

"Dems should demand Boehner remove this GOP Nazi reenactor," he wrote. "Put Boehner in this blitzkrieg."

This got another response from Clinton.

"I gave to Bill who is trying to influence strategy," she said.

Clinton's campaign team did not respond to a message from Business Insider on Monday evening asking whether this was a reference to President Bill Clinton. The Clinton campaign also did not respond to multiple requests for comment asking whether Clinton had a role crafting Democrats' strategy in the 2010 elections and whether she solicited advice on this from Blumenthal.

In some of his messages to Clinton on various topics, Blumenthal has taken credit for planting various stories in the media. He also did this in the lead-up to the 2010 election. Blumenthal indicated he "briefed" the writer of a Financial Times piece that praised President Clinton's performance on the campaign trail. In another message, he also claimed to have a role in a New Yorker piece by Sean Wilentz that criticized the tea party.

"Did this with Sean," Blumenthal wrote.

Blumenthal's most intense attack on Boehner came in what he described as a "post mid-terms strategy" memo that he sent Clinton on election day, November 2, 2010. Blumenthal described the lengthy missive as "what I hear from Republican sources and elsewhere and what it means for Republican strategy." He claimed there was extensive internal tension in the GOP. Blumenthal, who was charged with driving under the influence in New Hampshire while he was working on Clinton's 2008 campaign, also dismissed Boehner as "alcoholic."

"Boehner is despised by the younger, more conservative members of the House Republican Conference," Blumenthal wrote. "They are repelled by his personal behavior. He is louche, alcoholic, lazy, and without any commitment to any principle. Boehner has already tried to buy the members with campaign contributions and committee assignments, which he has already promised to potentially difficult members. His hold is insecure."

This post was updated at 8:20 a.m. with the statement from Boehner's office.