President of the United States, the head of the executive of the United States, is also the only executive officer who reaches his position by election; the appointment of the others being either in his hands (subject to their confirmation by the senate) or regulated by law. The president is elected for a term of four years; seven presidents—Washington, Jefferson, Madison, Monroe, Jackson, Lincoln, and Grant—have been chosen for a second term of office, but a third term, although there is nothing in the constitution to prevent it, is practically prohibited by the popular prejudice against it. A candidate must be a natural-born citizen of the United States, not under thirty-five years of age. The president has a salary of $50,000 a year, and must receive no other emolument during office from the United States or any state. He is commander-in-chief of the army and navy of the United States, and of the militia when in the actual service of the Union; he has the power to grant reprieves and pardons for offences against the United States, except in cases of impeachment, and (by and with the advice and consent of two-thirds of the senate) to make treaties and to appoint ambassadors, consuls, and all other officers of the United States whose appointments are not otherwise provided for; from time to time he sends to congress a 'message' (cf. the 'Queen's Speech') giving information as to the state of the Union, and recommending measures for consideration; he may convene both houses, or either house, in special session; and, if the two houses disagree as to the time of adjournment, he may adjourn them to such time as he thinks fit. The president, like the vice-president and all other civil officers, may be removed from office on impeachment by the House of Representatives for and conviction by two-thirds of the senate of treason, bribery, or other high crimes and misdemeanours. He may require the opinion, in writing, of the head of any of the executive departments on any subject relating to the duties of his department. Every bill which passes congress must have the president's signature to become a law, unless, after he has returned it with his objections, two-thirds of each house support it and pass it over his veto.
The Vice-president of the United States, although elected along with the president, is no part of the executive department. His sole function is to preside over the senate, where he has no vote unless in the case of a tie; and in practice he has little influence on the administration, and is regarded only as an 'under-study,' in readiness to take the presidency in the event of its being vacated by the president's removal, death, resignation, or inability. Four vice-presidents—Tyler, Fillmore, Johnson, Arthur—have so succeeded to the presidency. In the event of the removal, death, resignation, or inability of both the president and the vice-president, the secretary of state, and after him, in their order, other members of the cabinet, would act as president until the disability of the president was removed, or a new president elected. On the death of a vice-president the duties of his office are fulfilled by the president pro tempore of the senate.
The election of president and vice-president is controlled by the electoral system, under which the people do not vote directly for the candidates, but for electors from their separate states who are pledged to cast their votes for particular candidates. Each state is entitled to a number of electors equal to its number of senators (two in each case) and representatives in congress; these latter range from one to thirty-four (see table below). At first the electors simply voted for two candidates, and the one who received the second highest number of votes for president became vice-president; but since 1804 provision has been made for a separate election of the vice-president. In the event of no candidate having a majority of the electoral votes the House of Representatives chooses a president, voting by states, each state having one vote; if no vice-president is elected the senate chooses a vice-president, voting as usual. Such cases occurred in 1800-1, when Jefferson and Burr had tied, and the former was made president and the latter vice-president; in 1824-25, when none of the four candidates for the presidency had a majority, and John Q. Adams, who had received eighty-four electoral votes, was chosen by the House over Andrew Jackson, who had ninety-nine; and finally in 1836-37, when Richard M. Johnson, who had obtained a plurality of electoral votes for the vice-presidency, was elected by the senate. The territories have no vote in any case.
For other presidents, see the articles on the several republics that have such officers at the head of the government.
The presidents of the United States have been George Washington (1789-97), John Adams (1797-1801), Thomas Jefferson (1801-9), James Madison (1809-17), James Monroe (1817-25), John Quincy Adams (1825-29), Andrew Jackson (1829-37), Martin Van Buren (1837-41), William Henry Harrison (March-April 1841), John Tyler (1841-45), James Knox Polk (1845-49), Zachary Taylor (1849-50), Millard Fillmore (1850-53), Franklin Pierce (1853-57), James Buchanan (1857-61), Abraham Lincoln (1861-65), Andrew Johnson (1865-69), Ulysses S. Grant (1869-77), Rutherford Birchard Hayes (1877-81), James Abram Garfield (March-September 1881), Chester Alan Arthur (1881-85), Grover Cleveland (1885-89), Benjamin Harrison (1889-93), Cleveland (1893-97), William McKinley (1897, 1900). See separate articles. The following table shows the number of electoral votes allowed to each state since the census of 1890:
| Alabama.....11 | Maine.....6 | Ohio.....23 |
| Arkansas.....8 | Maryland.....8 | Oregon.....4 |
| California.....9 | Massachusetts.....15 | Pennsylvania.....32 |
| Colorado.....4 | Michigan.....14 | Rhode Island.....4 |
| Connecticut.....6 | Minnesota.....9 | South Carolina.....9 |
| Delaware.....3 | Mississippi.....9 | South Dakota.....4 |
| Florida.....4 | Missouri.....17 | Tennessee.....12 |
| Georgia.....13 | Montana.....3 | Texas.....15 |
| Idaho.....3 | Nebraska.....8 | Vermont.....4 |
| Illinois.....24 | Nevada.....3 | Virginia.....12 |
| Indiana.....15 | New Hampshire.....4 | Washington.....4 |
| Iowa.....13 | New Jersey.....10 | West Virginia.....6 |
| Kansas.....10 | New York.....36 | Wisconsin.....12 |
| Kentucky.....13 | North Carolina.....11 | Wyoming.....3 |
| Louisiana.....8 | North Dakota.....3 | Total.....444 |