Some context: William Charles Lunalilo was born on January 31, 1835 in a two-story house made of coral brick, an area known as Pohukaina, now part the grounds of the `Iolani Palace in Honolulu. His mother was High Chiefess Miriam Auhea Kekauluohi (later styled as Ka`ahumanu III) and his father was High Chief Charles Kana`ina. He was grandnephew of Kamehameha I by blood and the monarch's stepson by marriage to his mother. His grandmother was Kalakua Kaheiheimalie, sister of Kamehameha's favorite wife, Queen Ka`ahumanu.
King Kamehameha V, the last of the Kamehameha kings, died on December 11, 1872 without naming a successor. Under the Kingdom's 1864 constitution, if the king did not appoint a successor, a new king would be elected by the legislature from the eligible Hawaiian royals still alive. The other candidate was David Kalakaua. Lunalilo was the more popular of the two. His grandfather was Kalaimamahu, a half brother of Kamehameha I and was thus a cousin of King Kamehameha V. His grandmother was Queen Kalakua Kaheiheimalie, sister of Queen Ka`ahumanu. Because of this, many people believed the throne rightly belonged to Lunalilo since the only person more closely related to Kamehameha V, Bernice Pauahi Bishop, made clear she did not want the throne. Another contender was Princess Ruth Ke`elikolani who was a half sister to King Kamehameha V. She was a favorite among the Hawaiian chiefs because of her adhering to the old Hawaiian ways. She was governess of Hawaii and refused to speak English even though she was fluent in it. Her genealogy, however, was too controversial and few people considered her suitable to take the throne. This left Kalakaua and Lunalilo, and of the two, Lunalilo was greatly favored. So great was Lunalilo's popularity that some people believed that Lunalilo could have simply walked into the capital and declared himself king. Lunalilo, however, insisted that the constitution be followed. He issued the following message six days after the death of Kamehameha V:  "Whereas, it is desirable that the wishes of the Hawaiian people be consulted as to a successor to the Throne, therefore, notwithstanding that according to the law of inheritance, I am the rightful heir to the Throne, in order to preserve peace, harmony and good order, I desire to submit the decision of my claim to the voice of the people."  Lunalilo, unlike his more conservative opponent, wanted to amend the constitution to make the government more democratic by removing property qualifications for voting. It was decided that there would be a popular election to give the people a chance to have their voices heard. However, because the constitution gave the legislature the power to decide who would be the next king, the popular election would be unofficial. Lunalilo urged the people of the Kingdom to have their voices heard.  The popular vote was held on January 1, 1873 and Lunalilo won by an overwhelming majority. The week after, the legislature unanimously voted Lunalilo king. It has been speculated that the reason for the unanimous vote was because each legislator was required to sign his name on the back of his ballot, and the legislators were afraid to go against the wishes of the people. Queen Emma later wrote in a letter that hundreds of Hawaiians were ready to tear to pieces anyone who opposed Lunalilo.  At Lunalilo's investiture ceremony, held on January 9, 1873 at Kawaiaha`o Church, the courtyard was filled to capacity and a large crowd watched from outside. Because Lunalilo's popularity was so great, and because he became king through a democratic process, he became known as "The People's King."
How did Lunalilo win?
A: 

Some context: Sir Joseph Rotblat  (4 November 1908 - 31 August 2005) was a Polish physicist, a self-described "Pole with a British passport". Rotblat worked on Tube Alloys and the Manhattan Project during World War II, but left the Los Alamos Laboratory after the war with Germany ended. His work on nuclear fallout was a major contribution toward the ratification of the 1963 Partial Nuclear Test Ban Treaty. A signatory of the 1955 Russell-Einstein Manifesto, he was secretary-general of the Pugwash Conferences on Science and World Affairs from their founding until 1973, and shared, with the Pugwash Conferences, the 1995 Nobel Peace Prize "for efforts to diminish the part played by nuclear arms in international affairs and, in the longer run, to eliminate such arms."
Rotblat returned to Britain to become senior lecturer and acting director of research in nuclear physics at the University of Liverpool. Most of his family had survived the war. With the help of a Polish man, his brother-in-law Mieczyslaw (Mietek) Pokorny had created false Polish Catholic identities for Rotblat's sister Ewa and niece Halina. Ewa, taking advantage of the fact that she was an ash blonde who, like Rotblat, spoke fluent Polish as well as Yiddish, smuggled the rest of the family out of the Warsaw Ghetto. Mietek, Rotblat's brother Mordecai (Michael) and Michael's wife Manya, Rotblat's mother Scheindel, and two Russian soldiers lived in a concealed bunker underneath a house near Otwock, in which Ewa and Halina lived with a Polish family. Displays of Polish anti-Semitism that she witnessed during the Warsaw Ghetto uprising embittered Ewa towards Poland, and she petitioned Rotblat to help the family emigrate to England. He therefore now accepted Chadwick's offer of British citizenship so he could help them escape from Poland. They lived with him in London for some time before becoming established. Halina would go on to graduate from Somerville College, Oxford and University College London, and become an editor of the Dictionary of National Biography.  Rotblat felt betrayed by the use of atomic weapons against Japan, and gave a series of public lectures in which he called for a three-year moratorium on all atomic research. Rotblat was determined that his research should have only peaceful ends, and so became interested in the medical and biological uses of radiation. In 1949, he became Professor of Physics at St Bartholomew's Hospital ("Barts"), London, a teaching hospital associated with the University of London. He remained there for the rest of his career, becoming a professor emeritus in 1976. He received his PhD from Liverpool in 1950, having written his thesis on the "Determination of a number of neutrons emitted from a source". He also worked on several official bodies connected with nuclear physics, and arranged the Atom Train, a major travelling exhibition for schools on civil nuclear energy.  At St Bartholomew's, Rotblat worked on the effects of radiation on living organisms, especially on ageing and fertility. This led him to an interest in nuclear fallout, especially strontium-90 and the safe limits of ionising radiation. In 1955, he demonstrated that the contamination caused by the fallout after the Castle Bravo test at Bikini Atoll nuclear test by the United States would have been far greater than that stated officially. Until then the official line had been that the growth in the strength of atomic bombs was not accompanied by an equivalent growth in radioactivity released. Japanese scientists who had collected data from a fishing vessel, the Lucky Dragon, which had inadvertently been exposed to fallout, disagreed with this. Rotblat was able to deduce that the bomb had three stages and showed that the fission phase at the end of the explosion increased the amount of radioactivity by forty times. His paper was taken up by the media and contributed to the public debate that resulted in the ending of atmospheric tests by the Partial Nuclear Test Ban Treaty.
Why did he feel that way?
A:
Rotblat was determined that his research should have only peaceful ends, and so became interested in the medical and biological uses of radiation.