Washington (CNN)While House Speaker Nancy Pelosi on Tuesday announced a formal impeachment inquiry into President Donald Trump, there are some House Democrats who aren't fully on board yet.

       As the list of House Democrats who support the opening of an impeachment inquiry has climbed in recent days, these are the 18 House Democrats who have not made public statements in support of starting an impeachment inquiry or have only posited conditional support for it.

       Rep. Tom O'Halleran of Arizona

       Rep. Al Lawson of Florida

       Rep. Lucy McBath of Georgia

       Rep. Tulsi Gabbard of Hawaii

       Rep. Jared Golden of Maine

       Rep. Collin Peterson of Minnesota

       Rep. Jeff Van Drew of New Jersey

       Rep. Xochitl Torres Small of New Mexico

       Rep. Max Rose of New York

       Rep. Anthony Brindisi of New York

       Rep. Kendra Horn of Oklahoma

       Rep. Kurt Schrader of Oregon

       Rep. Conor Lamb of Pennsylvania

       Rep. Joe Cunningham of South Carolina

       Rep. Eddie Bernice Johnson of Texas

       Rep. Colin Allred of Texas

       Rep. Ben McAdams of Utah

       Rep. Ron Kind of Wisconsin

       This story will continue to update with additional developments.

       Rep. Tulsi Gabbard of Hawaii

       Rep. Jared Golden of Maine

       Rep. Collin Peterson of Minnesota

       Rep. Jeff Van Drew of New Jersey

       Rep. Xochitl Torres Small of New Mexico

       Rep. Max Rose of New York

       Rep. Anthony Brindisi of New York

       Rep. Kendra Horn of Oklahoma

       Rep. Kurt Schrader of Oregon

       Rep. Conor Lamb of Pennsylvania

       Rep. Joe Cunningham of South Carolina

       Rep. Eddie Bernice Johnson of Texas

       Rep. Colin Allred of Texas

       Rep. Ben McAdams of Utah

       Rep. Ron Kind of Wisconsin

       This story will continue to update with additional developments.