Standing in eligibility challenges
Several courts have ruled that private citizens do not have standing to challenge the eligibility of candidates to appear on a presidential election ballot. Alternatively, there is a statutory method by which the eligibility of the president-elect of the United States to take office may be challenged in Congress.
Some legal scholars assert that, even if eligibility challenges are nonjusticiable in federal courts, and are not undertaken in Congress, there are other avenues for adjudication, such as an action in state court in regard to ballot access.
 Presidential candidates whose eligibility was questioned
While every president and vice president to date is widely believed either to have been a citizen at the adoption of the Constitution in 1789 or to have been born in the United States, one U.S. president (Chester A. Arthur) and some presidential candidates either were not born or were suspected of not having been born in a U.S. state. In addition, one U.S. vice president (Albert Gore) was born in Washington, D.C., and another (Charles Curtis) was born in the Kansas Territory. This does not necessarily mean that they were ineligible, only that there was some controversy (usually minor) about their eligibility, which may have been resolved in favor of eligibility.
 Chester A. Arthur
Chester A. Arthur (1829–1886), 21st president of the United States, was rumored to have been born in Canada. This was never demonstrated by his Democratic opponents, although Arthur Hinman, an attorney who had investigated Arthur's family history, raised the objection during his vice-presidential campaign and after the end of his presidency. Arthur was born in Vermont to a Vermont-born mother and a father from Ireland, who was naturalized as a U.S. citizen in 1843, 14 years after Chester was born. Despite the fact that his parents took up residence in the United States somewhere between 1822 and 1824, Arthur additionally began to claim between 1870 and 1880 that he had been born in 1830, rather than in 1829, which only caused minor confusion and was even used in several publications. Arthur was sworn in as president when President Garfield died after being shot.
 Christopher Schürmann
Christopher Schürmann (born 1848 in New York) entered the Labor primaries during the 1896 presidential election. His eligibility was questioned in a New York Tribune article, because he was born to alien parents of German nationality. It was stated that "various Attorney-Generals of the United States have expressed the opinion that a child born in this country of alien parents, who have not been naturalized, is, by the fact of birth, a native-born citizen entitled to all rights and privileges as such". But due to a lack of any statute on the subject, Schürmann's eligibility was "at best an open question, and one which should have made [his] nomination under any circumstances an impossibility", because questions concerning his eligibility could have been raised after the election.
 Charles Evans Hughes
The eligibility of Charles Evans Hughes (1862–1948) was questioned in an article written by Breckinridge Long, and published in the Chicago Legal News during the U.S. presidential election of 1916, in which Hughes was narrowly defeated by Woodrow Wilson. Long claimed that Hughes was ineligible because his father had not yet naturalized at the time of his birth and was still a British citizen. Observing that Hughes, although born in the United States, was also a British subject and therefore "enjoy[ed] a dual nationality and owe[d] a double allegiance", Long argued that a native born citizen was not natural born without a unity of U.S. citizenship and allegiance and stated: "Now if, by any possible construction, a person at the instant of birth, and for any period of time thereafter, owes, or may owe, allegiance to any sovereign but the United States, he is not a 'natural-born' citizen of the United States."
 Barry Goldwater
Barry Goldwater (1909–1998) was born in Phoenix, in what was then the incorporated Arizona Territory of the United States. During his presidential campaign in 1964, there was a minor controversy over Goldwater's having been born in Arizona when it was not yet a state.
 George Romney
George Romney (1907–1995), who ran for the Republican party presidential nomination in 1968, was born in Mexico to U.S. parents. Romney's grandfather had emigrated to Mexico in 1886 with his three wives and children after the U.S. federal government outlawed polygamy. Romney's monogamous parents retained their U.S. citizenship and returned to the United States with him in 1912. Romney never received Mexican citizenship, because the country's nationality laws had been restricted to jus sanguinis statutes due to prevailing politics aimed against American settlers.
 Lowell Weicker
Lowell Weicker (born 1931), the former Connecticut senator, representative, and governor, entered the race for the Republican party nomination of 1980 but dropped out before voting in the primaries began. He was born in Paris, France to parents who were U.S. citizens. His father was an executive for E. R. Squibb & Sons and his mother was the Indian-born daughter of a British general.
 Róger Calero
Róger Calero (born 1969 in Nicaragua) was a Socialist Workers Party candidate in 2004 and 2008. Because he was not a natural born citizen of the United States, Calero was ineligible to become president, so James Harris, the Socialist Workers Party presidential candidate from 2000, stood in on the ticket in nine states where Calero could not be listed. In 2004, Calero received 3,689 votes, and Harris received 7,102 additional votes. Calero also ran in 2008, with Harris again standing in for Calero in several states. Calero was on the ballot in five states, where he received 7,209 votes; Harris received an additional 2,424 votes.
 John McCain
John McCain (born 1936), who ran for the Republican party nomination in 2000 and was the Republican nominee in 2008, was born at Coco Solo Naval Air Station in the Panama Canal Zone. McCain never released his birth certificate to the press or independent fact-checking organizations, but did show it to Washington Post reporter Michael Dobbs, who wrote "a senior official of the McCain campaign showed me a copy of [McCain's] birth certificate issued by the 'family hospital' in the Coco Solo submarine base". A lawsuit filed by Fred Hollander in 2008 alleged that McCain was actually born in a civilian hospital in Colon City, Panama. Dobbs wrote that in his autobiography, Faith of My Fathers, McCain wrote that he was born "in the Canal Zone" at the U.S. Naval Air Station in Coco Solo, which was under the command of his grandfather, John S. McCain Sr. "The senator's father, John S. McCain Jr., was an executive officer on a submarine, also based in Coco Solo. His mother, Roberta McCain, now 96, has vivid memories of lying in bed listening to raucous celebrations of her son's birth from the nearby officers' club. The birth was announced days later in the English-language Panamanian American newspaper."
The former unincorporated territory of the Panama Canal Zone and its related military facilities were not regarded as United States territory at the time, but 8 U.S.C. § 1403, which became law in 1937, retroactively conferred citizenship on individuals born within the Canal Zone on or after February 26, 1904, and on individuals born in the Republic of Panama on or after that date who had at least one U.S. citizen parent employed by the U.S. government or the Panama Railway Company; 8 U.S.C. § 1403 was cited in Judge Alsup's 2008 ruling, described below. A March 2008 paper by former Solicitor General Ted Olson and Harvard Law Professor Laurence H. Tribe opined that McCain was eligible for the Presidency. In April 2008, the U.S. Senate approved a non-binding resolution recognizing McCain's status as a natural-born citizen. In September 2008, U.S. District Judge William Alsup stated obiter in his ruling that it is "highly probable" that McCain is a natural-born citizen from birth by virtue of 8 U.S.C. § 1401, although he acknowledged the alternative possibility that McCain became a natural-born citizen retroactively, by way of 8 U.S.C. § 1403.
These views have been criticized by Professor Chin, who argues that McCain was at birth a citizen of Panama and was only retroactively declared a born citizen under 8 U.S.C. § 1403, because at the time of his birth and with regard to the Canal Zone the Supreme Court's Insular Cases overruled the Naturalization Act of 1795, which would otherwise have declared McCain a U.S. citizen immediately at birth. The U.S. State Department's Foreign Affairs Manual states that children born in the Panama Canal Zone at certain times became U.S. nationals without citizenship. It also states in general that "it has never been determined definitively by a court whether a person who acquired U.S. citizenship by birth abroad to U.S. citizens is a natural-born citizen […]". In Rogers v. Bellei the Supreme Court only ruled that "children born abroad of Americans are not citizens within the citizenship clause of the 14th Amendment", and didn't elaborate on the natural-born status. Similarly, legal scholar Lawrence Solum concluded in an article on the natural born citizen clause that the question of McCain's eligibility could not be answered with certainty, and that it would depend on the particular approach of "constitutional construction". The urban legend fact checking website Snopes.com has examined the matter and cites numerous experts. It considers the matter "undetermined".
 Barack Obama
Barack Obama (born 1961), 44th president of the United States, was born in Honolulu, Hawaii to a U.S. citizen mother and a British subject father from what was then the Kenya Colony of the United Kingdom (which became the independent country of Kenya in 1963). Before and after the 2008 presidential election, arguments were made that he is not a natural-born citizen. On June 12, 2008, the Obama presidential campaign launched a website to counter what it described as smears by his opponents, including conspiracy theories challenging his eligibility. The most prominent issue raised against Obama was the claim made in several lawsuits that he was not actually born in Hawaii. In two other lawsuits, the plaintiffs argued that it was irrelevant whether he was born in Hawaii, but argued instead that he was nevertheless not a natural-born citizen because his citizenship status at birth was governed by the British Nationality Act 1948. The relevant courts have either denied all applications or declined to render a judgment due to lack of jurisdiction. Some of the cases have been dismissed because of the plaintiff's lack of standing.
On October 31, 2008, Hawaii Health Director Dr. Chiyome Fukino issued a statement saying, "I ... have personally seen and verified that the Hawai'i State Department of Health has Sen. Obama's original birth certificate on record in accordance with state policies and procedures."  On July 27, 2009, Hawaii Health Director Dr. Chiyome Fukino issued a statement saying, "I ... have seen the original vital records maintained on file by the Hawaii State Department of Health verifying Barack Hussein Obama was born in Hawaii and is a natural-born American citizen." On April 27, 2011, the White House released a copy of President Obama's birth certificate.
An attempt to prevent Obama from participating in the 2012 Democratic primary election in New Hampshire failed. In October 2011, the Liberty Legal Foundation filed suit seeking to enjoin the Democratic National Committee from certifying Obama as its nominee for the 2012 U.S. presidential election on the ground that he does not have two citizen parents and thus, it contends, is not a natural-born citizen.