Most of the money for preconvention campaigns for presidential candidates comes from

from the super PAC (special political action committees.)

Explanation:

The major source of campaign financing is the Super PAC, the special political action committees.this organization is allowed by the Supreme Court to spend unlimited amounts of money on their preferred candidate. The money spent by Super PACs is part of a presidential campaign, although it does not represent money spent by the candidate.

a countries leader should be motivated by the common good of the country.