The Republican Party has been the party of wealth and privilege ever since the days of Harrison vs Cleveland. The GOP inherited the role of "business party" from the Whigs and the Know Nothings around the time of James K Polk. It was been the party of money, Protestantism and native born White folks since the times of Rutherford Hayes, whose election ended the occupation of the Siuth by the Freedmen's Bureau.
The Democratic Party is somewhat more complicated, as it has been the party of newcomers, and was the party of most Catholics until the time of Reagan's Southern Strategy. After the Civil War, the Republicans called the democrats the party of Rum, Romanism and Rebellion, since Republicans tended to be Protestants and supported the Union more than the Democrats, some of whom were Copperheads.
Since FDR, the Democrats have favored government support for the underprivileged, and after Reagan, this has become more important to the Democrats. Reagan's Southern Strategy was to ignore prosecution of the victims of the Klan and other White Power groups in the South, and that is why much of the South swing from Jim Crow Democrats to "They got too much already" Republicans, now more Grandsons of Jim Crow than Fathers of Jim Crow.
If you care about the environment and wise use of public lands, the Democrats favor this more.
If you love Big Oil, Big Banks, and Big Pharma and the Military Industrial Complex, the Republicans are your party.
Both parties have rich donors, but the Republicans have the ones who refuse to do anything to prevent the rich from get richer at the expense of the poor and middle class.