Rep. Jan Schakowsky (D) endorsed state Treasurer Alexi Giannoulias over the weekend, becoming the fifth Member of the state’s Congressional delegation to support the party’s frontrunner in the race for President Barack Obama’s former Senate seat.

“Alexi Giannoulias is the best candidate to retain President Obama’s seat because he has the courage to take on powerful interests and stand up for Illinois families,— Schakowsky said in a statement.

Schakowsky’s endorsement is important because it could help Giannoulias among female voters, especially in her liberal affluent North Shore district.

He faces former Chicago Urban League President Cheryle Robinson Jackson in the Democratic primary, and she has the backing of the influential women’s group EMILY’s List. Other candidates running in the February Democratic primary are former Chicago Inspector General David Hoffman and attorney Jacob Meister.

Among the state’s other Democratic Members backing Giannoulias are Reps. Luis Gutierrez, Phil Hare, Bill Foster and Mike Quigley. Reps. Danny Davis and Bobby Rush are supporting Jackson.

The winner of the Democratic primary is likely to face Rep. Mark Kirk (R) in the general election.