hard money in u.s. political elections refers to
Campaign finance in the United States Federal law restricts how much individuals and organizations may contribute to political campaigns, political parties, and other FEC-regulated organizations. Corporations and unions are banned from donating money directly to candidates ("hard money") or national party committees.[8]
Deposit (politics) In the typical case, the deposit collected is repaid to the candidate after the poll if the candidate obtains a specified proportion of the votes cast. The purpose of the deposit is to reduce the prevalence of 'fringe' candidates or parties with no realistic chance of winning a seat. If the candidate does not achieve the refund threshold, the deposit is forfeited.