By Emily Cadei, CQ-Roll Call

Former Massachusetts governor and 1988 Democratic presidential nominee Michael Dukakis endorsed Rep. Michael E. Capuano in the Democratic primary for the Senate special election Sunday at an event in Brookline, Mass.

Dukakis, the state’s longest-serving governor after serving from 1975-1979 and again from 1983-1991, joins his wife Kitty, in endorsing Capuano in the four-person race. The primary election is Dec. 8.

Dukakis expressed his support for Capuano at a town hall meeting Sunday in Brookline. It’s the first time since leaving office in 1990 that Dukakis has endorsed any Democrat running for statewide office in a primary.

In a statement issued by the Capuano campaign, Dukakis said he met the six-term congressman “as a young staffer at the State House,” then “watched him grow and develop into one of the best mayors in the Commonwealth” and “worked closely with him since his election to Congress.”

“Mike’s passion for public service and his dedication to his constituents are obvious. But it is his courage and his conviction on the important issues of the time that impress me most of all,” Dukakis said.

Massachusetts first lady Diane Patrick and Dukakis’ wife, Kitty, recently endorsed Capuano, though Gov. Deval Patrick is not endorsing anyone in the primary.

Capuano is scrambling to close the gap in the polls with Democratic frontrunner Martha Coakley, the state’s attorney general, in the next 10 days. The latest surveys of the primary field have him firmly in second place, ahead of investor and Boston Celtics co-owner Stephen Pagliuca and community service leader Alan Khazei.

Khazei rolled out his own set of endorsements from over 500 Massachusetts citizens and over 100 national leaders on Saturday at a “at statewide canvass kickoff” in Boston. Among his list of backers was Steve Case, co-founder and former CEO and Chairman of America Online, New York City Mayor Michael Bloomberg,Paul Fireman, the former CEO of Reebok, and film and television director [@J.J. Abrams.@http://www.imdb.com/name/nm0009190/@]

And on Sunday, the Boston Globe registered its support for Khazei.

On Friday, Coakley’s campaign announced the endorsement of four past and present elected officials from Somerville, Mass., a dig at Capuano, Somerville’s mayor from 1990-99.

The winner of the Democratic primary is expected to go on and win the general election on Jan. 19 to fill the seat previously held by Sen. Edward Kennedy.

CQ Politics rates the general election contest Safe Democratic.

To see how all the 2010 Senate races are shaping up, check out the CQ Politics election map