Democrat Katherine Clark has been sworn in as the state's newest member of Congress.

Clark took her oath of office Thursday at the Capitol in Washington, joined by U.S. Rep. Richard Neal, U.S. Sens. Elizabeth Warren and Edward Markey and other members of the state's congressional delegation. Clark is only the fifth woman ever elected to the U.S. House from Massachusetts.

Clark easily defeated three opponents in Tuesday's special election. She also resigned from her Melrose state Senate seat. An April 1 date has been set for a special election to fill Clark's seat.

Clark will represent the state's 5th Congressional District. The seat became vacant earlier this year when longtime Democratic U.S. Rep. Edward Markey won a special election to fill what had been Secretary of State John Kerry's Senate seat.

Clark will face re-election next fall.