DES MOINES — The latest round of federal COVID-19 relief is popular with the public, but Iowa U.S. Sen. Joni Ernst said Monday she believes Republicans will be able to sell their unanimous opposition to the package once the stimulus money has come and gone.The $1.9 trillion package includes, among other things, $1,400 stimulus payments to many Americans, an expansion of the child care tax credit in the form of payments to many American families, unemployment assistance, aid for state and local governments, funding for schools, food and housing assistance, and funding for vaccine production and testing.No congressional Republicans, including any from Iowa, voted in support of the package.But the legislation is popular with Americans: Seven out of 10 in a recent Pew Research Center poll said they favor the legislation.