Canadian news organizations are continuing to speculate on how a controversial memo that embarrassed Sen. Barack Obama (D-Ill.) on the campaign trail got leaked.

A Toronto Star columnist is floating a theory that a 1,300-word memo was leaked in March to The Associated Press by Frank Sensenbrenner, a former Canadian lobbyist and oldest son of Rep. F. James Sensenbrenner Jr. (R-Wis.).

This is not the first time a Canadian official has been linked to the leak. Canadian Prime Minister Stephen Harper's chief of staff, Ian Brodie, was also tied to the disclosure. An internal probe later cleared him.

The junior Sensenbrenner, reached today by The Post at his Alexandria home, called the Canadian reports "completely false" and said he did not see the memo until reading about in the press.

"The article was sourced by two unnamed sources and it's very hard to tell if someone is purposely trying to bring me into it," Sensenbrenner said. "Regardless, I did not leak the memo and I wasn't even under the engagement of the Canadian government at the time."

Sensenbrenner, 27, worked as a strategic analyst for Canada's Department of Foreign Affairs from January through April 2007. He is now pursuing a doctorate at the University of Sydney in Australia.

The senior Sensenbrenner, the 64-year-old former chairman of the House Judiciary Committee, has been re-elected 14 times since 1979 as a congressman from the wealthy Milwaukee suburbs.

The aforementioned memo, written by Canadian consulate official Joseph DeMora, described a meeting in Chicago between Canadian officials and Obama economic adviser Austan Goolsbee.

The memo says, among other things, that Goolsbee assured the Canadians that Obama is not as protectionist as he has sounded on the campaign trail:

"Noting anxiety among many U.S. domestic audiences about the U.S. economic outlook, Goolsbee candidly acknowledged the protectionist sentiment that has emerged, particularly in the Midwest, during the primary campaign," the memo said.

It continued: "He cautioned that this messaging should not be taken out of context and should be viewed as more about political positioning than a clear articulation of policy plans."

Goolsbee said the author of the memo misinterpreted the tenor of the meeting but aides to Sen. Hillary Rodham Clinton (D-N.Y.) quickly pounced on the issue, dubbing the episode "NAFTA-gate" and saying the incident raised "serious questions" about Obama.