As Joe Biden’s campaign faces questions about its lackadaisical outreach strategy, the former vice president’s campaign manager boasted on Tuesday about the campaign’s growing volunteer program. But Biden’s volunteer operation is still smaller than the one built during the primary by Bernie Sanders, with just seven weeks to go until the general election.

Democrats in swing states have started voicing concerns that the Biden campaign has not opened any stand-alone offices in battleground states and — unlike down-ballot Democrats — isn’t knocking doors. Biden’s campaign manager Jen O’Malley Dillon defended their outreach program on Tuesday in a live interview with Politico.

“We spend so much time talking about tactics, but, fundamentally, knocking on a door and not reaching anyone doesn’t get you much except leaving a piece of lit behind,” O’Malley Dillon said. “You might as well send a piece of mail.” She added: “We have 2,500 new volunteers that join the campaign every day.”