To many American voters, the dirty attacks of the 2016 election cycle are dizzying. Donald Trump has popularized the hashtag #CrookedHillary. Hillary Clinton characterizes Donald Trump as “temperamentally unfit and totally unqualified to be president.” Blows traded back and forth create a soap opera of vitriol and drama. And the voters can’t look away.

Political attacks are nothing new, however. In fact, they’re nearly as old as the country and are a staple of presidential election politics.

1828: John Q. Adams vs. Andrew Jackson

The 1828 election is commonly referred to as  “the dirtiest presidential campaign in U.S. history.” John Q. Adams and Andrew Jackson, though members of the Democratic-Republican Party, previously ran against each other in 1824, but the events of the campaign left a sour taste in Jackson's mouth.

The election of 1824 was one of the few elections in U.S. history that was decided by Congress because none of the 4 major candidates running secured an electoral win. It is widely believed, however, that U.S. House Speaker Henry Clay -- who also ran in the 1824 election -- made a deal with Adams and convinced enough members of the House to elect Adams in exchange for a cabinet position as secretary of state.

The deal between the two men became known as the "corrupt bargain of 1824," which resulted in the creation of the Democratic Party when Jackson and his faction revolted and broke away from the Democratic-Republicans.

By the time Jackson and Adams faced again in 1828, Adams had dirt on Jackson's past, and the two brought their rivalry public.

Jackson and Adams traded heated attacks. Adams supporters accused Jackson of murdering six of his own militiamen. Jackson supporters accused Adams of using public funds to buy a pool table and gamble in the White House. Jackson’s wife - who had been previously married - was accused of sinful adultery. Adams was accused of using prostitutes to gain favor in Russia during his time as ambassador.

In the end, Jackson won with 56 percent of the popular vote.

1912: William Howard Taft vs. Theodore Roosevelt vs. Woodrow Wilson

In 1912, two close friends and work partners, William Taft and Theodore Roosevelt, entered a brutal battle for the Republican nomination. The two once respected and close-knit candidates attacked each other ruthlessly with an onslaught of name-calling, criticizing each other over government regulations.

Roosevelt became the 26th President of the United States in 1901, after the assassination of William McKinley. He was then elected in 1904 and picked Taft to be his secretary of war, hoping they shared the same beliefs. Taft then became Roosevelt's personal choice to succeed him in the White House.

While in office, Roosevelt started the "Square Deal," a populist policy that pushed for greater equality in the workforce, increased rights for women, and emphasized environmental conservation. He hoped Taft, who had been close to the president, would continue his legacy.

However, things didn't go according to plan. Though Roosevelt helped Taft win the presidency in 1908, Taft tended to sympathize more with the conservative wing of the Republican Party over the progressive wing, which Roosevelt championed.

Roosevelt then left office for Africa, leaving Taft at the wheel of his endeavors. Not to mention, even before Roosevelt left Taft in charge, Roosevelt was already losing support within the party over his progressive movements.

After returning from a year-long safari in Africa, Roosevelt came back only to realize Taft had a much different approach to the presidency. The party began to crumble after the significant switch in policies between the two leaders. Pulling supporters in separate directions after Roosevelt left office, one Republican party divided into Taft or Roosevelt supporters -- conservatives or progressives.

The struggle for unity became evident to Taft, but not to Roosevelt. Taft continuously put all his effort into keeping the party together, but to no success. With no help from Roosevelt, the party diminished into two and the fight unraveled.

Feeling already beaten, Roosevelt had promised not to run for re-election but as time went on, his progressive constitutes requested his return. The political bitterness that would develop between the two men only escalated when they both decided to run for the Republican nomination in 1912.

Taft felt betrayed. But the race continued: one Republican, one Progressive, and one Democrat (Woodrow Wilson).

Taft argued Roosevelt would act as a “dangerous radical” and become “the most dangerous man in history,” according to his plans to create a more active government through his Square Deal reforms. Roosevelt struck back against Taft, saying he was a man of “political crookedness.”

The tension between the two became overwhelming after the votes were collected. Neither of the two had enough delegates to win, resulting in Roosevelt creating the Progressive Party, otherwise known as the "Bull Moose Party" to distance himself from Taft for a better chance in the election.

In the end, the constant fighting between the two men opened the door for Woodrow Wilson, a Democrat, to become the 28th President of the United States.

1964: Lyndon Johnson vs. Barry Goldwater

Cold War scares dominated the election of 1964, in which Republican Barry Goldwater, a former senator of Arizona, challenged President Lyndon Johnson for the Oval Office. During the campaign, Goldwater went so far as to accuse Johnson of "giving into communist aggression."

Goldwater thought Johnson was too passive while Johnson saw Goldwater as a war-driven fanatic. To Goldwater's surprise, Johnson did take action -- against him, and struck a blow so deep that the Republican candidate would never recover.

Johnson released the now infamous ‘Daisy Girl’ TV ad to send one message to the American people: Goldwater will lead the country into a nuclear war. In Goldwater’s defense, he responded “a choice, not an echo.”

Goldwater lost in a landslide. U.S News listed the 1964 presidential race as "one of the most consequential elections in History."

1984: Ronald Regan vs. Walter Mondale

Jimmy Carter's vice president, Walter Mondale, used a similar tactic as LBJ when he ran against President Ronald Reagan in 1984. In one ad, Mondale stated that a Reagan re-election would lead to nuclear war.

The tactic blew up in Mondale's face. Reagan was a popular incumbent who not only won re-election in a landslide, but won one of the biggest one-sided victories in presidential election history, taking 525 electoral votes to Mondale's 13. Mondale only won Minnesota and the District of Columbia, a brutal loss for a major party candidate.

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Today, candidates are under constant discrimination for their actions and as past elections show, the arena of presidential politics is an offensive playing field. The question is, will the 2016 race between the two major party candidates, Hillary Clinton and Donald Trump, join the list of most brutal campaigns in U.S. presidential history?

We will see.