This is how is the Electorial College works

https://www.archives.gov/federal-register/electoral-college/electors.html


What are the qualifications to be an Elector?
The U.S. Constitution contains very few provisions relating to the qualifications of Electors. Article II, section 1, clause 2 provides that no Senator or Representative, or Person holding an Office of Trust or Profit under the United States, shall be appointed an Elector. As a historical matter, the 14th Amendment provides that state officials who have engaged in insurrection or rebellion against the United States or given aid and comfort to its enemies are disqualified from serving as Electors. This prohibition relates to the post-Civil War era.

Each state's Certificates of Ascertainment confirms the names of its appointed electors. A state's certification of its electors is generally sufficient to establish the qualifications of electors.


Who selects the Electors?

Choosing each state's Electors is a two-part process. First, the political parties in each state choose slates of potential Electors sometime before the general election. Second, on Election Day, the voters in each state select their state's Electors by casting their ballots for President.

The first part of the process is controlled by the political parties in each state and varies from state to state. Generally, the parties either nominate slates of potential Electors at their state party conventions or they chose them by a vote of the party's central committee. This happens in each state for each party by whatever rules the state party and (sometimes) the national party have for the process. This first part of the process results in each Presidential candidate having their own unique slate of potential Electors.

Political parties often choose Electors for the slate to recognize their service and dedication to that political party. They may be state elected officials, state party leaders, or people in the state who have a personal or political affiliation with their party's Presidential candidate. (For specific information about how slates of potential Electors are chosen, contact the political parties in each state.)

The second part of the process happens on Election Day. When the voters in each state cast votes for the Presidential candidate of their choice they are voting to select their state's Electors. The potential Electors' names may or may not appear on the ballot below the name of the Presidential candidates, depending on election procedures and ballot formats in each state.

The winning Presidential candidate's slate of potential Electors are appointed as the state's Electors—except in Nebraska and Maine, which have proportional distribution of the Electors. In Nebraska and Maine, the state winner receives two Electors and the winner of each congressional district (who may be the same as the overall winner or a different candidate) receives one Elector. This system permits the Electors from Nebraska and Maine to be awarded to more than one candidate.

Are there restrictions on who the Electors can vote for?

There is no Constitutional provision or Federal law that requires Electors to vote according to the results of the popular vote in their states. Some states, however, require Electors to cast their votes according to the popular vote. These pledges fall into two categories—Electors bound by state law and those bound by pledges to political parties.

The U.S. Supreme Court has held that the Constitution does not require that Electors be completely free to act as they choose and therefore, political parties may extract pledges from electors to vote for the parties' nominees. Some state laws provide that so-called "faithless Electors" may be subject to fines or may be disqualified for casting an invalid vote and be replaced by a substitute elector. The Supreme Court has not specifically ruled on the question of whether pledges and penalties for failure to vote as pledged may be enforced under the Constitution. No Elector has ever been prosecuted for failing to vote as pledged.

Today, it is rare for Electors to disregard the popular vote by casting their electoral vote for someone other than their party's candidate. Electors generally hold a leadership position in their party or were chosen to recognize years of loyal service to the party. Throughout our history as a nation, more than 99 percent of Electors have voted as pledged.

List of State Laws and Requirements Regarding the Electors

verified as of March 1, 2016

The Office of the Federal Register presents this material for informational purposes only, in response to numerous public inquiries. The list has no legal significance. It is based on information compiled by the Congressional Research Service. For more comprehensive information, refer to the U.S. Constitution and applicable Federal laws.

Legal Requirements or Pledges
Electors in these States are bound by State Law or by pledges to cast their vote for a specific candidate:

ALABAMA – Party Pledge / State Law – § 17-19-2
ALASKA – Party Pledge / State Law – § 15.30.040; 15.30.070
CALIFORNIA – State Law – Elections Code § 6906
COLORADO – State Law – § 1-4-304
CONNECTICUT – State Law – § 9-175
DISTRICT OF COLUMBIA – DC Pledge / DC Law – § 1-1001.08(g)
FLORIDA – Party Pledge / State Law – § 103.021(1)
HAWAII – State Law – §§ 14-26 to 14-28
MAINE – State Law – § 805
MARYLAND – State Law – § 8-505
MASSACHUSETTS – Party Pledge / State Law – Ch. 53, § 8, Supp.
MICHIGAN – State Law – §168.47 (Violation cancels vote and Elector is replaced.)
MISSISSIPPI – Party Pledge / State Law – §23-15-785(3)
MONTANA – State Law – § 13-25-304
NEBRASKA – State Law – § 32-714
NEW MEXICO – State Law – § 1-15-5 to 1-15-9 (Violation is a fourth degree felony.)
NORTH CAROLINA – State Law – § 163-212 (Violation cancels vote; elector is replaced and is subject to $500 fine.)
OHIO – State Law – § 3505.40
OKLAHOMA – State Pledge / State Law – 26, §§ 10-102; 10-109 (Violation of oath is a misdemeanor, carrying a fine of up to $1000.)
OREGON – State Pledge / State Law – § 248.355
SOUTH CAROLINA – State Pledge / State Law – § 7-19-80 (Replacement and criminal sanctions for violation.)
VERMONT – State Law – title 17, § 2732
* VIRGINIA – State Law – § 24.1-162 (Virginia statute may be advisory – “Shall be expected” to vote for nominees.)
WASHINGTON – Party Pledge / State Law – §§ 29.71.020, 29.71.040, Supp. ($1000 fine.)
WISCONSIN – State Law – § 7.75
WYOMING – State Law – §§ 22-19-106; 22-19-108