Former NYC Mayor Rudy Giuliani has formally endorsed US Senate hopeful David Malpass, who is locked in a three-way primary battle for the right to take on Democratic Sen. Kirsten Gillibrand on Row B in November.

This nod, which was delivered via press release, comes in spite of the fact that Malpass parted ways back in July Giuliani’s 2008 presidential campaign manager, Mike DuHaime.

“David Malpass is a serious thinker who will serve in the tradition of some of New York’s most distinguished United States senators,” said Giuliani.

“David is a life-long fiscal conservative who has stayed true to his principles of limited government, low taxes and strong economic growth throughout his entire career, dating back to his service to President Reagan. I’m thrilled to endorse him as the next U.S. Senator because I know he will be a leader that New Yorkers can be proud of.”

Malpass seems to be gaining some traction in advance of next week’s primary. He was endorsed by the Post last week.