BOSTON — Supreme Judicial Court Chief Justice Ralph Gants is planning to join hundreds of attorneys from more than 40 law firms to lobby state lawmakers for funding for civil legal aid programs for low-income Massachusetts residents.

The event, known as the Annual Walk to the Hill for Civil Legal Aid, is planned for Thursday at the Massachusetts Statehouse.

This year, participants are pushing for a $5 million increase for the Massachusetts Legal Assistance Corporation — the largest funder of civil legal aid in Massachusetts — for a total appropriation of $23 million.

Advocates said that about 880,000 people in Massachusetts have incomes at or below 125 percent of the federal poverty level — or $30,750 a year for a family of four — making them eligible for civil legal aid.