Senator Obama talks about the plan here:
Rather than explain it, you can read the actual plan and it's words here:
Who May Vote Absentee?
Per § 24.2-700 of the Code of Virginia, the following registered voters may vote by absentee ballot in any election in which they are qualified to vote:
Any person who, in the regular and orderly course of his business, profession, or occupation or while on personal business or vacation, will be absent from the county or city in which he is entitled to vote;
Any person who is (i) a member of a uniformed service of the United States, as defined in 42 U.S.C. § 1973ff-6(7), on active duty, or (ii) a member of the merchant marine of the United States, or (iii) who temporarily resides outside of the United States, or (iv) the spouse or dependent residing with any person listed in (i), (ii), or (iii), and who will be absent on the day of the election from the county or city in which he is entitled to vote. See Absentee Voting Procedures for Overseas Personnel (Military & Non-Military)
Any student attending a school or institution of learning, or his spouse, who will be absent on the day of election from the county or city in which he is entitled to vote;
Any person who is unable to go in person to the polls on the day of election because of a disability, illness or pregnancy ;
Any person who is confined while awaiting trial or for having been convicted of a misdemeanor, provided that the trial or release date is scheduled on or after the third day preceding the election. Any person who is awaiting trial and is a resident of the county or city where he is confined shall, on his request, be taken to the polls to vote on election day if his trial date is postponed and he did not have an opportunity to vote absentee;
Any person who is a member of an electoral board, registrar, officer of election, or custodian of voting equipment;
Any duly registered person who is unable to go in person to the polls on the day of the election because he is primarily and personally responsible for the care of an ill or disabled family member who is confined at home; or
Any duly registered person who is unable to go in person to the polls on the day of the election because of an obligation occasioned by his religion.
Any person who, in the regular and orderly course of his business, profession, or occupation, will be at his place of work and commuting to and from his home to his place of work for eleven or more hours of the thirteen that the polls are open (6:00 AM to 7:00 PM).
Any registered and qualified voter may request a mail ballot for presidential and vice-presidential electors only by writing across the top of their absentee application "request ballot for presidential electors only." A voter who votes a "presidential only" ballot may not later decide to vote the rest of the ballot. The same procedures and deadlines apply as for other absentee applications and ballots.
New registrants who submitted their voter registration applications by mail must vote in person (either in-person absentee or at the polls on election day) unless the voter is a full time college student, absent active duty military, residing overseas, physically handicapped, age 65 or over (however, they must also list a qualifying reason for voting absentee, as age itself does not qualify a voter for an absentee ballot), or voting a "presidential only" ballot.
Any voter with a question about whether they qualify to vote absentee, or how to apply, should contact their local elections office.
How Do I Apply for an Absentee Ballot?
Overseas Personnel (Military & Non-Military) See Absentee Voting Procedures for Overseas Personnel (Military & Non-Military)
You can contact your local Voter Registration Office to request an absentee ballot application. You can either return the completed application to your local voter registration office either by mail or fax. The absentee ballot application must be received in your local voter registration office by the Tuesday before election day to receive a ballot by mail.
Alternatively, you can download The Virginia Absentee Ballot Application (on-line fillable pdf format). Or, if you are an absent active duty military voter (or spouse/dependent) or overseas voter you should download the Federal Post Card Application instead of the Virginia application. You must have the Adobe™ Acrobat Reader installed on your computer to view or print either portable document formatted (pdf) application. If you do not have Adobe™ Acrobat Reader installed on your computer, you can download and install the Adobe™ Acrobat Reader free of charge. After downloading the application form: 1) print the form, 2) read the instructions accompanying the form, 3) fill out the requested information on the form carefully, 4) sign the form and, 5) mail or fax the completed application to your local general registrar's office by the Tuesday before election day to receive a ballot by mail. (Note, if you email or fax the Federal Post Card Application, you must then mail the signed original to your local registrar, as it also serves as your registration application.)
Completing an absentee ballot application
Virginia law prescribes that Applications for absentee ballots shall be completed in one of the following manners:
1) In Person
An application completed in person shall be made not less than three days prior to the election in which the applicant offers to vote and completed only in the office of the local general registrar. The applicant shall sign the application in the presence of a registrar or the secretary of the electoral board.
By mail, electronic or telephonic transmission to a facsimile device
Applications can be made by mail, electronic or by fax, if one is available to the office of the local general registrar. If a facsimile device is not available locally contact us . The application shall be sent to the appropriate local general registrar not less than seven days prior to the election in which the applicant offers to vote.
How often must you complete an absentee ballot application?
You must complete a separate absentee ballot application for each election in which you intend to vote absentee.
Exception: You may file a single Federal Post Card Application at any time after the November general election to receive ballots for all elections that you are eligible to vote in during the next calendar year, if you are:
(i) a member of a uniformed service of the United States, as defined in 42 U.S.C. § 1973ff-6(7), on active duty, or
(ii) a member of the merchant marine of the United States, or
(iii) temporarily residing outside of the United States (but eligible for permanent registration in Virginia -- that is, your Virginia place of abode is still available to you whenever you return to Virginia), or
(iv) the spouse or dependent residing with any person listed in (i), (ii), or (iii) above.
Important Notice:
Your Federal Post Card Application will serve as your absentee ballot application for all elections that you are eligible to vote in for the next two regularly scheduled general federal elections. This means that you will receive absentee ballots automatically! It also means you are responsible for informing your local registrar of all and any address changes.
If you have any questions or should require individual assistance, please do not hesitate to contact Vickie R. Williams by phone at 804-864-8932 or via email at vickie.williams @sbe.virginia.gov.