Health care and financial security, two issues especially important to seniors, top the agenda of an AARP forum Thursday night in Iowa featuring five Democratic presidential candidates.

All the major candidates except Barack Obama are scheduled to take part in the event at the historic Adler Theatre before an audience of 2,300. The forum also is being sponsored by Iowa Public Television and will be broadcast live from Davenport on PBS stations in the state as well as on 265 public television stations throughout the nation, although many of those broadcasts will be on a delayed basis.

PBS correspondent Judy Woodruff will moderate the forum.

AARP spokeswoman Nancy LeaMond said the debate offers seniors “the opportunity to hear the candidates engage in a robust discussion on the issues that matter most to them.”

Health care and financial security are top concerns for many Americans, but especially seniors, who are among the most likely to vote in Iowa’s leadoff precinct caucuses.

The AARP has 390,000 members in Iowa. Although the group doesn’t endorse candidates, it works to educate members on politics and issues. AARP has asked members to submit questions, and more than 1,000 have been offered.

Senate votes were keeping three of the candidates in Washington on Thursday, but event organizers said they expected all of those who had committed to the 7 p.m. CDT event to attend.

Those planning to participate are Sens. Joe Biden, Hillary Rodham Clinton and Chris Dodd, former Sen. John Edwards and New Mexico Gov. Bill Richardson. Obama, whose campaign announced last month that he would limit his participation in such joint appearances, will arrive in Iowa on Friday for two days of events.

Debate organizers did not invite Democrats Dennis Kucinich and Mike Gravel to the forum. Though they are candidates for the Democratic presidential nomination, neither has an active campaign in Iowa.

A similar forum for Republican candidates is set for Oct. 25 in Sioux City, Iowa.