How is the support rate of the president of the United States counted?

President Meitu's support rate is counted through polls.

Polls are generally organized by specialized polling agencies, such as Gallup, as well as major media, major newspapers and university research institutions around the world. National polls such as the US presidential election are mainly conducted independently or jointly by big polling agencies and big media.

The main method of polling is very simple. By using the most basic statistical sampling theory, that is, randomly selecting a group of voters from all voters to understand their voting tendency, we can get the intention of the national voters. If it is a close election, you can only draw a one-sided conclusion by asking anyone casually, but when you look for tens of thousands of people, the average result is quite accurate. For example, if Obama's approval rate is 5 1% from 10,000 people, then his true approval rate should have a 95% probability between 50% and 52%. This is called the confidence interval. Generally speaking, polls rarely use so many samples. If more than 1000 samples are collected, the 95% confidence interval just mentioned can be controlled within plus or minus 3%. The average national poll should be at least this number or higher, or even tens of thousands. In contrast, polls in this state are often hundreds of people, because of the resource constraints of organizers.

The president of the United States is elected by the national voters, but not directly by the voters, but by the electoral college system. Voters voted for 538 electors representing 50 states and the District of Columbia. A presidential candidate can win by winning more than half of the electoral votes (at least 270). Except Maine and Nebraska, which distribute electoral votes according to the percentage of votes, the other 48 States and the District of Columbia all implement the "winner takes all" system, that is, all electoral votes in the state are given to the presidential candidate who gets the most electoral votes in the state. In this case, calculate the support rate of the presidential candidate.

States in the United States have the same number of electors as senators and representatives in Congress. The Senate consists of two members elected by each state, while the number of members in the House of Representatives is determined according to the population proportion of each state. A populous state has more representatives and more electoral votes in the presidential election. For example, California, the most populous state, has as many as 55 electoral votes, while Alaska and other less populous States have only three electoral votes. Although the District of Columbia has no Senate or House of Representatives, it still has three electoral votes.

The primary election is the first stage of the American presidential election, which usually starts at the beginning of the election year and ends in the middle of the year. There are two forms of pre-selection, namely, grass-roots meetings of political parties and direct pre-selection. The former means that the two parties hold a representative meeting in each state from the bottom up, and advance step by step from the election point, county, constituency to the state, and finally choose their own representatives to participate in the national congress. The latter is like universal suffrage in form. Voters from both parties in a state go to the polling station on the same day to vote for their deputies to the national congress, which is the primary election method adopted by most States at present.

After the primary election, the two parties usually hold national congresses in July and August respectively. The main task of the meeting is to finalize the party's presidential and vice presidential candidates, discuss and adopt the presidential campaign platform. After the National Congress, the presidential campaign officially kicked off. This process usually lasts 8 to 9 weeks. During this period, the presidential candidates of the two parties will spend a lot of money traveling around the country, advertising, making campaign speeches, meeting voters, holding press conferences and holding public debates. In addition, candidates will also elaborate their policy propositions on internal affairs and foreign affairs in various forms to win the trust of voters and win votes.