Washington (CNN) -- Sex, lies and murder. Americans seem to love conspiracy theories and too-good-to-be-true rumors -- type "George W. Bush IQ" into Google and watch what you get -- especially when it comes to politics.

Did you know that George Washington wasn't the nation's first president? The Mob killed JFK. And, oh yeah, President Obama wasn't born in Hawaii.

All fun to talk about. And all wrong or at least without proof.

CNN takes a look at 11 political conspiracies, myths and urban legends and helps you tell fact from fiction.

1) The myth: George Washington wasn't the first U.S. president.

The facts: Theorists say it was actually John Hanson, the president of the Continental Congress, who served as the nation's first president, not George Washington.

That claim is simply false.

The office of "President of the United States" was created under the Constitution in 1787, long after Hanson died.

2) The rumor: George W. Bush has the lowest IQ of all the presidents.

The facts: A report by the Lovenstein Institute in 2001 found that George W. Bush had the lowest IQ of any president in the past 50 years. The report was discovered on the website lovenstein.org.

The problem? There is no Lovenstein Institute and no report.

Case solved.

3) The myth: Washington Redskins always predict the presidential winner.

The facts: The claim is that, since 1936, the outcome of the Washington Redskins' last home game before the presidential election has predicted the outcome of who wins the White House.

The way it works: If the Redskins lose, the incumbent party loses; if they win, the incumbent wins.

Although the circumstances have worked out for 17 elections in modern history, it is just another political superstition that pundits love to use -- or maybe to fill time.

In 2004, the Redskins lost to the Green Bay Packers 28-14 on October 31. Under the myth, incumbent President George W. Bush should have lost to Democratic Sen. John Kerry.

That was not the case. Kerry lost, too.

4) The myth: Sarah Palin didn't give birth to baby Trig.

The facts: Soon after Alaska Gov. Sarah Palin was announced as Sen. John McCain's 2008 presidential running mate, rumors abounded that her newborn son, Trig, who was born with Down syndrome, was not hers.

The McCain campaign, along with Palin herself, shot down the rumor.

Conspiracy theorists, now called "Trig Truthers," point to photos taken in late March of that year in which Palin's stomach appears, they say, to be flat -- not the image of an expectant mother. But other photos show her with a round stomach.

Then there's the question of why Palin waited so long to seek medical attention after her water broke during a trip to Texas. Reports indicate that it took more than 15 hours for her to get to a hospital after flying back to Alaska.

Some claimed that the baby, born in April, might have been that of teenage daughter Bristol. But Bristol gave birth to her own child, Tripp, in December. Myth busted.

5) The theory: The government was behind the September 11 attacks.

The facts: The September 11 terrorist attacks have become a lightning rod for conspiracy theorists who have offered alternative explanations to the horror of that day.

Some of the theories include that the U.S. government was behind the entire terror plot, including taking down the World Trade Center, in order to take the country to war in the Middle East; the Pentagon was not hit by a commercial plane but rather by a missile; and United Flight 93 did not crash after passengers stormed the cockpit, but an Air Force jet took it out.

Popular Mechanics magazine looked into the claims and was able to "debunk each of these assertions with hard evidence and a healthy dose of common sense."

6) The myth: Sen. John McCain had an illegitimate black child.

The facts: There was an effort during the 2000 GOP presidential primaries to start a smear campaign against John McCain, who was running a tight race against George W. Bush in South Carolina, saying the Arizona senator had an illegitimate black child.

In an interview with NBC's "Today Show" last year, political operative Karl Rove, who was said to have been behind the story, shot down the claim. He said he had "nothing to do" with the rumor, adding that it came from "a professor at Bob Jones University" and not the Bush campaign.

McCain and his wife, Cindy, have an adopted daughter from Bangladesh.

Bush ended up winning South Carolina 53% to 42%.

7) The charge: The Clintons were responsible for the death of Vince Foster.

The facts: In summer 1993, Vince Foster, deputy White House counsel in the Clinton administration and close friend to the first couple, was found dead in a federal park in northern Virginia. Investigators ruled it a suicide.

In 1994, the Arkansas Project -- an effort to discredit the Clintons -- raised the idea that the couple was responsible for the murder of Foster and others who may have had incriminating evidence against the former Arkansas governor.

Three investigations into the death turned up no evidence of a link. The Clintons have emphatically denied any involvement. The rumor, however, found its way into the media and GOP circles.

8) The charge: Rep. Gary Condit was involved in Chandra Levy's disappearance.

The facts: The 2001 disappearance of Chandra Levy, an intern for the federal Bureau of Prisons, drew national attention after her parents discovered a connection with then-Rep. Gary Condit, D-California.

He was never a suspect in the case but was questioned intensively for details as to Levy's whereabouts. Condit was also rumored to have had a sexual relationship with Levy an allegation he repeatedly refused to answer.

But Condit's semen was found on her underwear, according to an FBI biologist who testified at a trial in 2010.

Levy's body was found in a Washington park more than a year after her disappearance. Salvadoran immigrant Ingmar Guandique -- who was in prison for another crime -- was convicted in her killing and sentenced in 2011 to 60 years in prison.

9) The theory: Someone besides Lee Harvey Oswald killed JFK.

The facts: Decades after President John F. Kennedy's assassination in Dallas, the shooting and the events that followed continue to fascinate many Americans.

Much of that interest rests on the theory that the assassination was the result of a conspiracy -- not the act of a lone gunman, Lee Harvey Oswald.

Theories include that Kennedy "was killed by CIA agents acting either out of anger over the Bay of Pigs or at the behest of Vice President Lyndon Johnson," by the KGB or by "mobsters mad at Kennedy's brother for initiating the prosecution of organized crime rings," according to Time magazine.

But the Warren Commission, established to investigate the assassination, found that Oswald was the lone gunman -- and that there was not a second shooter.

10) The myth: President Zachary Taylor was poisoned to death.

The facts: Taylor, the nation's 12th president, was rumored to have died after being poisoned with arsenic, possibly by his wife.

But the claim was debunked by DNA scientists in 1991.

Medical officials in Kentucky ruled that he was not poisoned but rather died because of natural causes, such as gastroenteritis. The results were obtained after testing Taylor's tissue samples.

"The question of whether he was poisoned or not will no longer hang over us," Coroner Richard F. Greathouse of Jefferson County told the New York Times. "We've put that to rest once and for all."

Arsenic was found, but state officials said it was in levels too low to be considered deadly.

11) The myth: Barack Obama wasn't born in the U.S.

The facts: CNN has investigated these claims by "birthers" who say the nation's 44th president was not born in America and thus is not eligible to be president.

The Obama team and the state of Hawaii released a certification of live birth that documents the president's birth on August 4, 1961, in Honolulu. This is not the original birth certificate but is a valid legal document. In Hawaii and other states, original birth certificates are not released when requested later.

The certificate, officials say, allows a person born in Hawaii to get a driver's license, purchase land and obtain a U.S. passport.

The "birthers" claim that Obama doesn't want to show the birth certificate because it may claim that he wasn't born in America.

But state officials -- including Gov. Neil Abercrombie and Dr. Chiyome Fukino, the former director of Hawaii's Department of Health -- said they saw the document, and Obama was born in the U.S.

In addition, his birth announcement appeared in two Honolulu papers. The announcements are provided to the newspapers by the Department of Health and not members of the public, according to officials.