Sen. Susan Collins and Sen. Rev. Raphael Warnock both tested positive for COVID-19 late Thursday after casting their vote to confirm Supreme Court Justice Ketanji Brown Jackson, making them the latest in a string of Washington D.C. power players to contract the virus. Collins, R-Maine, and Warnock, D-Ga., are experiencing only mild symptoms. But their presence on the floor of the Senate for the historic vote raises concerns that other lawmakers and perhaps even Vice President Kamala Harris could have been exposed and may test positive in coming days. Michael LaRosa, the spokesman for first lad…