Universal Right to Vote by Mail Act of 2008 - Amends the Help America Vote Act of 2002 to prohibit a state from imposing additional conditions or requirements on the eligibility of an individual to cast a vote in federal elections by mail, except to the extent that it imposes a deadline for requesting the ballot and returning it to the appropriate state or local election official.
Prohibits a state from accepting and processing such an absentee ballot unless it verifies the identification of the individual's signature on the ballot by comparing it with the individual's signature on the official list of registered voters in the state.