WASHINGTON — Penalties levied by the Federal Election Commission for campaign finance violations have plummeted to record lows even as political spending has soared, according to newly released data from the agency.

The statistics underscore the sharp decline in enforcement at the commission, which has come under fresh scrutiny because of partisan gridlock. By law, each party has three commissioners, resulting in recent years in a 3-to-3 vote on virtually any significant issue.

Republicans on the commission say they believe the drop in fines shows that campaigns are generally following the law as a result of better training and compliance programs. Democrats say it is a troubling sign of lax enforcement.

The chairwoman of the commission, Ann M. Ravel, a Democrat, said in an interview published Sunday in The New York Times that because of the gridlock, she was largely abandoning hope of reining in campaign finance abuses in the 2016 presidential election.