How hard is it to amend the Constitution? Imagine last year's health care battle, multiplied by 50.

Sen. Lindsey Graham (R-S.C.) recently said he would like to see the repeal of the 14th Amendment, which allows children born in the United States to automatically become citizens even if their parents are not legal residents.

The suggestion has caused quite an uproar among immigration activists, pundits and other lawmakers, but if history is any guide, nothing is likely to come of it.

Amendments must be passed by a two-thirds vote of both chambers of Congress and then approved by three-fourths of all 50 state legislatures. (The president has no formal role.) In addition, Congress can put a deadline on a proposed amendment, so if it is not approved within, say, seven years, the proposal is dead.

That's been the fate of a handful of amendments lucky enough to make it that far in the process. Dozens of others are introduced each year without even getting through one chamber of Congress.

Over the past half-century, amendments which have passed have been ones for which there was an unusual amount of agreement or a perfect political storm.

This week, Congress.org took a look at the stories behind some of the many efforts to amend the Constitution: with success, with near-success, and with failure.

Successful amendments

Amendment Lowering the Voting Age to 18

As the increasingly unpopular Vietnam war raged on, fewer numbers of eligible men were enlisting for service. The draft was put in place and thousands of young men who were barely out of high school were forced into the army.

But the 18-year-olds being sent overseas to fight and possibly die for their country could not even vote for the lawmakers sending them there because the voting age at that point was 21.

"Old enough to fight, old enough to vote," became the slogan used by those who favored lowering the voting age in the late 1960s.

Ultimately, in 1971, Congress passed the resolution establishing the creation of the 26th Amendment, which guarantees any American citizen the right to vote who is at least 18 years of age. The states ratified it in the shortest time ever.

The constitutional amendment was, in addition, also intended to override a 1970 Supreme Court decision that ruled that states could set their own age limits for local elections.

Amendment Limiting U.S. Presidents to Only Two Terms

George Washington set the precedent for holding only two terms in office when he declined to seek a third, but no law existed to keep presidents from serving more until 1951.

Ulysses S. Grant and Theodore Roosevelt both attempted to run for third terms unsuccessfully, but most other presidents voluntarily quit after two terms.

After being elected president four times, Franklin Delano Roosevelt died from a cerebral hemorrhage barely into the start of his final term. Congressional Republicans who had lived through the 12-year presidency argued that it was a bad precedent and in 1947 passed the 22nd Amendment out of Congress.

By 1951, it had been ratified by the states, but some have questioned the wisdom of the amendment since.

Members of Congress, including House Majority Leader Steny H. Hoyer (D-Md.) have made moves in recent years to repeal the two-term limit, but those resolutions have not gained much traction.

Amendments that were never ratified

District of Columbia Voting Rights Amendment

District of Columbia license plates boast the phrase "Taxation without Representation." It's a reference to the fact that Washington, D.C., residents pay taxes just like residents of other states but, unlike residents of other states, do not having voting members of Congress to represent them.

This almost changed with the 1978 passage of a Constitutional amendment to give statehood status to D.C., along with two senators and at least one House member. Constituents currently rely on one, non-voting delegate to articulate local concerns in Congress.

Following the resolution's passage, however, only 16 states ratified the amendment before time expired.

A major concern was that a change in the make-up of the Electoral College would benefit Democrats, as D.C. voters have always heavily tilted towards that party.

And it was still a concern in this Congress, when the House—with the backing of President Obama—appeared poised to vote in favor of legislation, rather than a constitutional amendment, guaranteeing D.C. statehood.

In exchange for the creation of likely Democratic seats, Utah would have been granted a new, likely Republican, seat.

But the bill was pulled from the floor at the eleventh hour due, in part, to the fact that House bill would have to reflect the Senate-passed version that included language nullifying most of D.C.'s gun control laws.

That new provision, like giving Utah an additional electoral vote, was a move to appease Republicans who support the right to bear arms.

Equal Rights Amendment

Though at first glance the Equal Rights Amendment seems relatively uncontroversial—it would guarantee that all the laws apply equally to men and women—the push for its passage has been a 90-year effort that continues today.

Congress only passed the amendment once, in 1972, before it failed ratification, just shy of three states.

The amendment was first brought to Congress in the early 1920s thanks to suffragist Alice Paul, who believed the 19th Amendment, which guarantees women the right to vote, did not do enough to ensure the absence of gender discrimination.

Though it was introduced in every subsequent Congress thereafter, it was not adopted by both chambers until 1972.

Until that time, even feminists who would otherwise have supported Constitutional amendments guaranteeing gender equality were wary, arguing that women needed unique government protection independent of their relationship to men.

Critics also worried that the language of the amendment would override labor protections, many intended expressly for women workers.

When the amendment did pass the House and Senate, it was after a decade of heavy campaigning on its behalf.

But the amendment was never ratified, even after the expiration date of 1979 was extended through the middle of 1982 so that proponents could work on shoring up backing by other states.

In the end, one of the major reasons why the amendment fell short of support was that opponents saw the language, in its simplicity, as opening the floodgates to the invalidation of countless laws and precedents, from deeming the all-male military draft as unconstitutional to banishing single-sex public restrooms.

Unsuccessful amendments

Flag Desecration Amendment

Though everyone agrees that freedom of speech should be protected, lawmakers have for decades wondered if the freedom to burn American flags should be exempt.

Congress has, in fact, been exploring avenues to ban the practice in the constitution since 1989, when the Supreme Court ruled that such a ban would violate First Amendment rights to free expression. Though President George H.W. Bush signed a bill into law that year overturning the decision, the court stepped back in to strike it down on the same grounds in 1990.

Since that time and up until Democrats regained control of both chambers in 2006, Republican have spearheaded resolutions that would amend the Constitution to ban the act once and for all, calling the practice a slap in the face to American values.

The House was able to move the resolutions forward each time they were introduced, albeit largely along party lines. But the measures could never surmount the necessary two-thirds-support hurdle in the Senate, where too many senators believed it would hurt freedom of speech.

In some cases, the resolutions were voted down; in others, they languished without even being considered, supporters knowing they didn't have the votes to succeed.

Amendment to Define Marriage as "Between One Man and One Woman"

Like efforts to ban American flag desecration, efforts to constitutionally bar same-sex marriage were, during the early to mid-2000s, driven by Republican-led Congresses and laid to rest once Democrats came to power.

In 2004, Republicans hoped the resolution would put Sen. John Kerry (D-Mass.) in an uncomfortable position since he was running against President George W. Bush as the Democratic nominee, and his sure vote against a constitutional ban on gay marriage could sway some undecided voters against him.

And in 2006, a year that threatened to remove a Republican majority from the House and Senate, Republican lawmakers wanted to use the resolution to energize their conservative base.

But while most lawmakers, like today, did not want to come out in full favor of gay marriage for fear of alienating more conservative constituents, they were still reluctant to support a sweeping constitutional amendment on the issue.

As a result, enough moderate Republicans sided with Democrats on the "no" side so that the resolutions never advanced.

Emma Dumain writes for Congressional Quarterly.

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