Factbox-A state-by-state guide to US early voting

Voting machines are shown at Hillsborough County supervisor of elections office

WASHINGTON (Reuters) - By the time Democratic U.S. Vice President Kamala Harris faces Republican Donald Trump in the Nov. 5 presidential election, millions of Americans likely will have already cast their ballots at early voting centers.

Most states offer some form of in-person early voting, which allows voters to avoid Election Day crowds. Early voting has already started in Pennsylvania, Virginia, South Dakota and Minnesota.

The following is a timetable when other states kick off in-person voting:

Sept. 26

Illinois

Oct. 7

California, Montana, Nebraska, Maine

Oct. 8

Indiana, New Mexico, Ohio, Wyoming

Oct. 9

Arizona

Oct. 15

Georgia

Oct. 16

Iowa, Rhode Island, Tennessee

Oct. 17

North Carolina

Oct. 18

Louisiana, Washington

Oct. 19

Nevada, Massachusetts

Oct. 21

Alaska, Arkansas, Colorado, Connecticut, South Carolina, Texas

Oct. 22

Hawaii, Missouri, Utah, Wisconsin

Oct. 23

West Virginia

Oct. 24

Maryland

Oct. 25

Delaware

Oct. 26

Florida, Michigan, New Jersey, New York

Oct. 28

District of Columbia

Oct. 30

Oklahoma

* Not all states offer in-person early voting. In some states, in-person, early voting entails dropping off a ballot at a local government office. Within states, not all counties offer early voting.

(Reporting by Jason Lange in Washington; Editing by Bill Berkrot)