Democrats pressure and lobby pollsters to skew polls in their favor, discourage Republican vote. Media early call for Gore in 2000 kept Florida panhandle voters from voting since they thought it was over. 2012, Obama DOJ sues Gallup

In April 2012 Obama campaign manager Axelrod complained publicly about Gallup methodology that showed Romney ahead. After Gallup declined to change its methods, Obama DOJ sued Gallup on another matter.

 9/21/12, "What John McLaughlin Sees in the Polls Right Now," NRO, Jim Geraghty 
Interview with Republican pollster John McLaughlin: 

"How campaigns try to sway polling results: “In a close race, the operatives are trying to manipulate the turnout through their paid and earned media. The earned media includes lobbying and trying to skew the public polls. Historically the most egregious case was the 2000 Gore campaign’s lobbying the networks’ exit pollsters for an early, and wrong, call in Florida. This suppressed the Florida Panhandle and Western state turnout.” …
What Obama and his allies are doing now:

“The Democrats want to convince [these anti-Obama voters] falsely that Romney will lose to discourage them from voting. So they lobby the pollsters to weight their surveys to emulate the 2008 Democrat-heavy models. They are lobbying them now to affect early voting. IVR [Interactive Voice Response] polls are heavily weighted. You can weight to whatever result you want. Some polls have included sizable segments of voters who say they are ‘not enthusiastic’ to vote or non-voters to dilute Republicans. Major pollsters have samples with Republican affiliation in the 20 to 30 percent range, at such low levels not seen since the 1960s in states like Virginia, Florida, North Carolina and which then place Obama ahead. The intended effect is to suppress Republican turnout through media polling bias.  

We’ll see a lot more of this."...via Legal Insurrection 

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9/6/12, "Justice Dept. Gallup lawsuit came after Axelrod criticized pollsters," Daily Caller, Matthew Boyle

"Internal emails between senior officials at The Gallup Organization, obtained by The Daily Caller, show senior Obama campaign adviser David Axelrod attempting to subtly intimidate the respected polling firm when its numbers were unfavorable to the president.

After Gallup declined to change its polling methodology, Obama’s Department of Justice hit it with an unrelated lawsuit that appears damning on its face.

TheDC is withholding the identities of the Gallup officials to protect them from potential retaliation from Obama’s campaign and his administration.

In April, Axelrod tweeted that a poll showing Mitt Romney with a 48-43 percent lead over Obama was “saddled with some methodological problems,” directing his Twitter followers to read a National Journal story criticizing Gallup polls showing a Romney lead.
In that National Journal piece, Ron Brownstein wrote that the polls showing Romney leading the president had “a sample that looks much more like the electorate in 2010 than the voting population that is likely to turn out in 2012.”

Internally, Gallup officials discussed via email how to respond Axelrod’s accusations. One suggested that it “seems like a pretty good time for a blog response,” and named a potential writer.
In response to that suggestion, another senior Gallup official wrote — in an email chain titled “Axelrod vs. Gallup” — that the White House “has asked” a senior Gallup staffer “to come over and explain our methodology too.”"...

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