The poster child for claims that polls are wrong. (Melina Mara/The Washington Post)

At some point in every doomed political campaign, as Election Day gets uncomfortably close, the motivating hope switches from "We're gaining ground in the polls" to "The polls aren't reflecting what's happening." Sometimes that switch is made simply to ensure that volunteers keep showing up. Sometimes it's optimism that has overflowed the bounds of rationality. And sometimes it's self-delusion.

In Iowa on Sunday, Democrats responded to a new poll from the Des Moines Register that showed their candidate, Bruce Braley, trailing Republican Joni Ernst by a wide margin. "That’s not the number we are seeing on the ground," state party Chairman Scott Brennan told MSNBC. Retiring Democratic Sen. Tom Harkin had another take. "I’ve been in politics long enough, folks, and in enough races to know that there’s always one poll – they just catch people on the wrong night, or they just don’t do their due diligence in their calling, and we have an outlier," he said. "This is one of the outlier polls. It just doesn’t fit into anything we know." Braley's analysis? "You know the only poll that I’m counting on?" he told supporters. "It’s the poll right here in my gut."

The Register poll, with Ernst up seven points, is different from other polls. A Fox News Channel survey out Monday showed Ernst at 45 percent to Braley's 44 percent. So, it's possible that what Democrats are seeing (or say they're seeing) on the ground reflects movement that the poll doesn't capture. But the odds of that are very, very slim.

We took a quick tour of recent elections to figure out how often the mantra "The polls are wrong" comes into play -- and how often the polls actually were wrong. Presented below, quotes from the media and elected officials about races, along with the actual race results.

(A note: There probably are others that didn't get picked up in our search. And we didn't include rants from celebrities, such as when filmmaker Michael Moore said in 2004 that John Kerry would win the presidency because "The polls are wrong. They are all over the map like diarrhea. You are being snookered if you believe any of these polls." Moore was incorrect.)

2002. Race: South Dakota, governor. Candidate: Jim Abbott

"With all due respect, the poll is wrong, that's all I can say, it's just wrong."
(Source: Argus Leader)

Was the poll wrong? No. Margin of defeat: 15

2002. Race: Connecticut, CT-05. Candidate: James Maloney

Internal polls, and a newspaper poll to be released Saturday, show the race is much closer, Maloney said. "It's a single-digit race," he said.
(Source: AP)

Was the poll wrong? No. Margin of defeat: 11

2002. Race: Texas, governor. Candidate: Tony Sanchez

"The public polls have been wrong consistently. The race is much tighter than that. The turnout is going to be good for the entire Democratic ticket."
(Source: AP)

Was the poll wrong? No. Margin of defeat: 17.8

2002. Race: Colorado, Senate. Candidate: Wayne Allard

Republicans insist public polls are wrong and their guy is fine.
(Source: New York Post)

Was the poll wrong? Yes. Margin of victory: 4.9

2004. Race: Tennessee, president. Candidate: John Kerry

"This is the first election where the polls and the street heat don't match," said Stephen Lindsey, who works with the Davidson County Democrats and the Democratic National Committee. "The polls are wrong."
(Source: AP)

Was the poll wrong? No. Margin of defeat: 14.3

2006. Race: House. Speaker: George W. Bush

"Well, if their election forecasts are as good as their economic forecasts, we're going to have a great day on November the 7th."
(Source: Agence-France Presse)

Was the poll wrong? No. Margin of defeat: Lost 30 seats

2006. Race: Tennessee, Senate. Candidate: Harold Ford Jr.

Democrats, in particular, are stressing their unprecedented get-out-the-vote drive to argue that independent polls are wrong in showing that Republican Bob Corker has pulled ahead of Democrat Harold Ford Jr. in the contentious campaign that conceivably will decide which party controls the U.S. Senate.
(Source: Knoxville News-Sentinel)

Was the poll wrong? No. Margin of defeat: 2.7

2006. Race: New Jersey, Senate. Candidate: Tom Kean Jr.

On a classic fall campaign day in Sussex County, Kean also predicted victory, saying recent polls were wrong. Tieless and wearing an orange Barbour jacket and khaki pants, he declared he "absolutely will win."
(Source: Newark Star-Ledger)

Was the poll wrong? No. Margin of defeat: 9

2006. Race: Massachusetts, Governor. Candidate: Kerry Healey

"This has been a very fluid race, if you believe polls," she said recently. "And I don't always believe polls."
(Source: Sentinel & Enterprise)

Was the poll wrong? No. Margin of defeat: 20

2008. Race: President. Candidate: John McCain

"Those polls have consistently shown me much farther behind than we actually are. We're doing fine. We have closed [the gap] in the last week. We continue to close this next week. You're going to be up very, very late on election night."
(Source: Financial Times)

Was the poll wrong? No. Margin of defeat: 7.2

2010. Race: Oklahoma, governor. Candidate: Jari Askins

"The reason they [her opponent's campaign] are pushing all of the polling numbers stuff is because they think they're big-time ahead," Hudson said. "But I can tell you, just like I told people in the primary, these polls are wrong."
(Source: The Oklahoman)

Was the poll wrong? No. Margin of defeat: 21

2010. Race: Kentucky, Senate. Candidate: Jack Conway

"This won't be the first time I've overcome an erroneous Courier-Journal poll," he said, adding that the poll samples too many Republicans and too few Democrats. "I've earned a reputation as a closer."
(Source: Courier-Journal)

Was the poll wrong? No. Margin of defeat: 11.4

2010. Race: New York, Ggvernor. Candidate: Carl Paladino

"The polls were wrong in the primary by 27 points," Paladino told a group of 40 supporters at the Jefferson County GOP headquarters in Watertown, north of Syracuse. "The polls can't judge the turnout, and we're trying to get everybody out. ... That's the key to this."
(Source: Newsday)

Was the poll wrong? No. Margin of defeat: 29.3

2010. Race: California, governor. Candidate: Meg Whitman

But she continued to insist that her campaign's internal polls, which she says show her in a "dead heat," are right -- and that the Field, Public Policy Institute of California and Los Angeles Times/USC polls are wrong.
(Source: Contra Costa Times)

Was the poll wrong? No. Margin of defeat: 12.9

We'll close with 2012, and a quote from ABC's Matthew Dowd, railing against claims from allies of Mitt Romney that the polling that year was "skewed."

"The first thing happens is, don't believe -- the public polls are wrong. That's the first sign of a campaign that's about to lose. The second thing, we're going to change the nature of the electorate, and you're not seeing it reflected in the polls. And the third thing is, the only poll that counts is Election Day. When you hear those things, you know you're about to lose."

Was every poll wrong in 2012? No.