SAN DIEGO -- Six of the eight Democratic presidential candidates are scheduled to participate in a forum Thursday on issues affecting the lives of gay, lesbian, bisexual and transgender Americans.

The candidates will appear separately in alphabetical order, each answering questions for 15 minutes at a Hollywood television studio.

Topics are expected to include same-sex marriage, the "Don't ask, don't tell" policy barring openly gay and lesbian individuals from serving in the armed forces, hostility and discrimination in the workplace, and partners' health care and inheritance rights.

The only Democratic presidential candidates who will not participate are Sens. Joseph Biden, D-Del., and Christopher Dodd, D-Conn., who cited scheduling conflicts, said Brad Luna, director of communications for the Human Rights Campaign. His group, the nation's largest civil rights organization working to achieve gay, lesbian, bisexual and transgender equality, is the forum organizer.

The Dodd campaign will post his responses to the questions posed on the Web site, www.chrisdodd.com.

"Thursday's discussion represents an important and historic step for the nation because addressing equal rights and responsibilities for the GLBT community is fundamental to fulfilling America's promise," Dodd said.

Even before the forum was held, the author of a proposed initiative that would enshrine California's same-sex marriage ban in the state constitution called the field of Democratic presidential candidates "strong advocates of the transsexual-bisexual-homosexual agenda, which is blatantly attacking marriage for a man and a woman."

"It's obvious that these politicians cannot be trusted to protect what's good and right as an example for impressionable children," Randy Thomasson said.

"California voters must rise up to override these pandering politicians on the ballot in order to protect marriage rights for one man and one woman, once and for all."

But Luna said there is no political risk to the candidates involved in today's forum.

The year "2008 is not 2004," Luna said.

"The country has moved steadily and at lightning speed toward equality," he said. "Divisive wedge politics in terms of gay issues is not what it was before and that's indicative of the type of questions these candidates are being asked.

"No longer are we discussing a federal marriage amendment, but we're actually talking about ways we can progress toward equality."

Organizers initially hoped to also have a forum for Republican candidates, inviting the top three in the polls -- former New York City Mayor Rudy Giuliani, former Massachusetts Gov. Mitt Romney and Arizona Sen. John McCain. But only Romney responded, and he rejected the invitation, Luna said.

Questionnaires "on some top issues dealing with equal rights" were earlier sent to all the Democratic and Republican presidential campaigns, and no Republican candidate responded, Luna said.

The two-hour forum will be televised live by the Logo cable channel and on Visiblevote08.com, a Logo-affiliated Web site devoted to politics.

Questioning the candidates will be Washington Post editorial writer Jonathan Capehart, singer Melissa Etheridge, and Human Rights Campaign President Joe Solmonese. Bloomberg News columnist Margaret Carlson will be the moderator.