Section 1. The District constituting the seat of Government of the United States shall appoint in such manner as the Congress may direct:
A number of electors of President and Vice President equal to the whole number of Senators and Representatives in Congress to which the District would be entitled if it were a State, but in no event more than the least populous State; they shall be in addition to those appointed by the States, but they shall be considered, for the purposes of the election of President and Vice President, to be electors appointed by a State; and they shall meet in the District and perform such duties as provided by the twelfth article of amendment.
Section 2. The Congress shall have power to enforce this article by appropriate legislation.
This established representation of Washington, DC in the Electoral College for presidential elections. Passed by Congress in 1960, this was ratified in 1961. Although originally considered neutral, with the exception of one "faithless elector" in 2000 all three of DC's Electoral College votes have been for the Democratic Party.
Amendments to the Constitution of the United States of America
Bill of Rights:
1 - Freedom of speech, press, religion, etc.
2 - Right to bear arms
3 - Quartering of soldiers
4 - Warrants
5 - Due process
6 - Right to a speedy trial
7 - Right by trial of a jury
8 - No cruel or unusual punishments
9 - Unenumerated rights
10 - Power to the people and states
11 - Immunity of states to foreign suits
12 - Revision of presidential election procedures
13 - Abolition of slavery
14 - Citizenship
15 - Racial suffrage
16 - Federal income tax
17 - Direct election of the United States Senate
18 - Prohibition of alcohol
19 - Women's suffrage
20 - Terms of the presidency
21 - Repeal of Eighteenth Amendment
22 - Limits the president to two terms
23 - District of Columbia Voting for President
24 - Prohibition of poll taxes
25 - Presidential disabilities
26 - Voting age lowered to 18
27 - Variance of congressional compensation