Islanders will get a chance tomorrow morning to learn first-hand about the four Democratic candidates looking to fill the Massachusetts seat in the U.S. Senate that was left vacant when longtime Massachusetts Sen. Edward M. Kennedy died in August.

A candidates forum will be held tomorrow morning at the Howes House in West Tisbury from 9:30 to 11:30 a.m. None of the candidates is expected to attend, although each will send a representative. At press time yesterday, it was still unclear who would attend the forum on behalf of each candidate.

The Democratic primary to fill the seat is on Dec. 8 and the special election is on Jan. 19. Senator Kennedy died on August 25 of brain cancer; the Senate seat he had held since 1962 was filled by interim appointee Paul Kirk, a longtime Kennedy aide who will not run for election to complete the term.

There are four Democratic candidates: Massachusetts Attorney General Martha Coakley, Stephen Pagliuca, a managing partner of the Boston Celtics, U.S. Rep. Mike Capuano, and Alan Khazei, cofounder and former chief executive officer of City Year.

There are also two Republican candidates: Scott P. Brown and Jack E. Robinson 3rd. All four Democrats share similar views on what has quickly become the central issue of the campaign: health care reform. Like Senator Kennedy before them, all support some version of national health care reform, although they disagree on what is the best plan.

The Affordable Health Care for America Act was passed by the House last week by a narrow margin.

Ms. Coakley is arguably the most experienced of the four candidates, having served as district attorney of Middlesex County from 1999 to 2007 before being elected as the first woman to serve as attorney general of Massachusetts. She also has ties to the Island and is a seasonal resident in West Tisbury.

Ms. Coakley is a strong supporter of green energy technologies, and led an 18-state coalition to oppose a 2007 U.S. Supreme Court ruling that the Environmental Protection Agency does not have the authority to regulate greenhouse gases under the Clean Air Act.

Earlier this year she filed a lawsuit against the U.S. Department of Health and Human services challenging the constitutionality of the Defense of Marriage Act. The complaint claims that Congress overstepped its authority and undermined states’ efforts to recognize marriage between same-sex couples.

Mr. Capuano represents the 8th district of Massachusetts, a seat once held by John F. Kennedy and Tip O’Neill, which includes the northern three-fourths of Boston plus Cambridge and Somerville. In 2006 he was appointed chairman of the Task Force on Ethics Enforcement by Speaker Nancy Pelosi, with whom he has a close relationship.

Mr. Capuano is strongly pro-choice and was critical of the Stupak-Pitts Amendment that places limits on taxpayer-funded abortions in the Affordable Health Care for America Act. He initially voted for the act, but changed his position saying he would not support the final bill with the amendment intact.

Mr. Pagliuca has framed himself as a Beltway outsider, free from special interest influence, who would lean heavily on his business background to solve the nation’s ongoing economic problems. In addition to being a managing partner of the Boston Celtics, he is also the managing director of the private equity firm Bain Capital.

This week he launched a statewide radio campaign targeting both Ms. Coakley and Mr. Capuano for saying they would vote against any final health care bill if it restricts federal funding for abortion.

Mr. Khazei is probably the least known of the four candidates, and has cited his relative newcomer status to politics as a strength. He is founder and CEO of Be the Change Inc., a Boston-based organization dedicated to building national coalitions of nonprofits and citizens to enact legislation on issues such as poverty and education.

He cofounded City Year with Michael Brown, his friend and roommate at Harvard College and Harvard Law School. The company engages 17 to 24-year-olds in a year of service in one of 19 U.S. cities and in Johannesburg, South Africa. In 2006 U.S. and World Report named Mr. Khazei one of America’s 25 Best Leaders.

He opposes legislation on Beacon Hill to license casino gambling.