Former state senator John Chichester — a powerful Republican who headed the Senate Finance Committee — has endorsed a pair of Democratic senate candidates in Northern Virginia.

Chichester was often at odds with members of his own party and teamed up with then-Gov. Mark Warner (D) to approve higher taxes in exchange for new investments in education, public safety and health care. He represented the Fredericksburg area for almost three decades until he retired in 2008.

On Wednesday, Chichester threw his support behind Democrat Shawn Mitchell, who is running in a newly-drawn district representing parts of Prince William and Loudoun counties, against Republican Dick Black.

Chichester called Mitchell an “independent thinker’’ who will not be swayed by his party, caucus or by any ideological interests to cast votes not beneficial to all the people he represents or to the state.

Last week, Chichester came out for Democratic Sen. Toddy Puller, who faces former delegate Jeff Frederick (R) for a seat representing parts of Fairfax and Prince William counties.

“Senator Puller did not approach issues as a Republican or a Democrat but what would work best for the people of Virginia,’’ Chichester said in a statement. “She carefully considers the facts about the issues and works to keep the state fiscally strong by ensuring Virginia is able to provide the core services government is tasked to do.”