Maryland Gov. Martin O'Malley, left, and House Speaker Michael E. Busch, take their seats at the start of a bill signing ceremony last month.. (AP Photo/Cliff Owen)

The event has been scheduled to coincide with a four-day convention of the Maryland Municipal League, which is expected to draw more than 1,500 local officials and corporate sponsors to the popular beach town.

O’Malley has been active raising money around the country for Marylanders for Marriage Equality, the group leading the effort to uphold the state’s new same-sex marriage law in an expected November referendum. On several recent out-of-state trips as chairman of the Democratic Governors Association, O’Malley has held separate fundraisers to aid the cause in Maryland.

Tuesday’s fundraiser in Ocean City will be Busch’s first time as a host. A former civil unions supporter, Busch said last year that he had “evolved” on the issue. He played a key role shepherding the legislation through the House of Delegates this year.

Tickets to the event at the Galaxy 66 Bar and Grill start at $1,000.