Story highlights The Democrats fundraising has lagged since Barack Obama left office

The $3.8 million the DNC raised in July was its worst month since January 2009

(CNN) Former President Barack Obama is set to hold a fundraiser for the Democratic National Committee -- the first time he'll raise money for the party and just his second political event overall since leaving office, a Democratic Party official told CNN on Friday.

The fundraiser, set for September 27 in Washington according to a Democratic Party official, is expected to help Obama's former labor secretary, DNC Chairman Tom Perez, bolster the party's lagging fundraising numbers and pump money into state parties and Virginia races this fall.

Invites to party donors are going out Friday afternoon.

Obama's first in-person foray back into politics since leaving the White House came in July, when he attended a small, private fundraiser at a house in Washington for the National Democratic Redistricting Committee, the new group led by former Attorney General Eric Holder.

Since then, Obama has tweeted about politics and events, including Charlottesville and the decision to end the Deferred Action for Childhood Arrivals program. But his criticism of President Donald Trump has only been implicit, and he has not used Trump's name.

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