The couple got married in Washington on Friday, Cheney and his wife, Lynne, said in a statement, AP reported.
Mary and Poe have been in relationship for many years and have two children. The Cheneys said they were delighted that they could take advantage of the “opportunity to have the relationship recognized.”
The District of Columbia and six states — Connecticut, Iowa, Massachusetts, New Hampshire, New York and Vermont — have legalized gay marriage.
In the 2004 election, Republicans backing the ticket of President George W. Bush and Cheney pushed for state ballot initiatives rejecting gay marriage. More recently, President Obama expressed his support for same-sex marriage.