| Order: | Member of the U.S. House of Representatives from New York's |
| Term Start: | March 4, 1921 |
| Term End: | March 3, 1923 |
| Predecessor: | John B. Johnston |
| Successor: | Loring M. Black, Jr. |
| Order1: | Acting Mayor of New York City |
| Term Start1: | September 10, 1913 |
| Term End1: | December 31, 1913 |
| Predecessor1: | William Jay Gaynor |
| Successor1: | John Purroy Mitchel |
| Order2: | President of the Board of Aldermen |
| Term Start2: | 1912 |
| Term End2: | 1913 |
| Predecessor2: | John Purroy Mitchel |
| Successor2: | George McAneny |
| Order3: | Vice-Chairman of the Board of Aldermen |
| Term Start3: | 1912 |
| Term End3: | 1912 |
| Order4: | New York City Alderman |
| Constituency4: | 51st District (Brooklyn) |
| Term Start4: | 1904 |
| Term End4: | 1907, 1912–1913, and January 1–6, 1914 |
| Birth Name: | Ardolph Loges Kline |
| Birth Date: | 21 February 1858 |
| Birth Place: | Newton, New Jersey, U.S. |
| Death Place: | New York City, New York, U.S. |
| Party: | Republican |
| Spouse: | Frances A. Phalon (m. November 25, 1886) |
| Profession: | merchant, military officer, government official |
| Alma Mater: | Phillips Academy, Andover, Massachusetts |
Ardolph Loges Kline (February 21, 1858 – October 13, 1930) was an American politician and New York National Guard officer who became acting Mayor of New York City on September 10, 1913, upon the death of Mayor William Jay Gaynor,[1] serving for the rest of the year. He was later a United States representative from Brooklyn (1921–1923).
Kline was born near Newton, New Jersey, in 1858 and studied at Phillips Academy in Andover, Massachusetts, but did not attend college. In 1876 and 1877, he started working for a men's clothing company in New York City and joined the New York National Guard as a private. When the Spanish–American War of 1898 began, he was named a Lieutenant-Colonel, and in 1901 a Brevet (honorary or acting) Brigadier-General.
After losing a campaign for Sheriff of Kings County (Brooklyn), Kline was elected as an Alderman for the 51st District in Brooklyn in 1903 and 1905, but lost re-election in 1907 due to Democratic redrawing of his district. He won back his seat in 1911 and became Vice-Chairman of the Board of Aldermen in 1912, promising to enforce all rules fairly from the chair (including those against smoking).[2]
When John P. Mitchel, the elected President of the Board of Aldermen, resigned in 1912 in order to become Collector of the Port of New York, Kline succeeded Mitchel. And when Mayor Gaynor (who had never fully recovered from an attempted assassination in 1910) died at sea in September 1913, Board President Kline became mayor.
He served out the remainder of Gaynor's term, leaving office on December 31, 1913. Despite his stated intention of keeping all the department heads appointed by his predecessor for the rest of his term, Kline, in his very last days of office, dismissed Rhinelander Waldo as Commissioner of Police rather than accept a New Year's Eve resignation.[3]
Although re-elected as alderman for his old district for the 1914–1915 term, Kline resigned in early January 1914 to begin four years as the City's Tax Commissioner for Brooklyn (reviewing appeals of property tax assessments).[4]
He later served as a Republican U.S. Representative from New York (5th District in Brooklyn) from 1921 to 1923, being named to the House Committee on Naval Affairs,[5] but lost re-election in 1922 to Loring M. Black, Jr. (Democratic, 1923–1935). Kline spent all of his post-Congressional life as New York manager of the sea-service bureau of the United States Shipping Board.
Kline died October 13, 1930, at the Methodist Episcopal Hospital in Brooklyn, New York,[6] and was buried in Holy Cross Cemetery.
He is still (in early 2016) the only mayor of the consolidated (post-1897) city never to have won a citywide popular election to any office (such as those from which Joseph V. McKee and Vincent Impellitteri rose to become acting mayor). On the other hand, Kline is also the last serving or former mayor to win election to any other public office.
Here are the election returns from the Fifth Congressional District in Brooklyn for 1920–1922, as reported by William Tyler Page, the Clerk of the United States House of Representatives.[7] The sitting Democratic Representative, John B. Johnston (1919–21), did not seek re-election in 1920.
| year | candidate | party | vote | percent | |
| 1920 | Ardolph L. Kline | Republican | 42,129 | 58.2% | |
| Edward Cassin | Democratic | 27,650 | 38.2% | ||
| Israel M. Chatcuff | Socialist | 2,047 | 2.8% | ||
| William M. Nichol | Prohibition | 574 | 0.8% | ||
| 72,400 | |||||
| 1922 | Ardolph L. Kline | Republican | 25,917 | 42.1% | |
| Loring M. Black, Jr. | Democratic | 33,840 | 54.9% | ||
| Louis Weil | Socialist & Farmer-Labor | 1,412 | 2.3% | ||
| William M. Nichol | Prohibition | 428 | 0.7% | ||
| 61,597 | |||||