The phrase "potential runoff" refers to the possibility of excess water flowing over the ground's surface instead of being absorbed into the soil. Full definition
This was then reflected in 2010 with the Eurozone debt crisis with sovereigns hoarding their cash reserves at their central bank in case of potential runoffs on their bonds and deposits. (lawyer-monthly.com)
The Associated Press had not called the race as of midnight, and even de Blasio steered clear of discussing the potential runoff in favor of focusing on the next phase of the race. (dnainfo.com)
Ryan noted that the potential runoff for the Reform Party, which holds open primaries, would be open to approximately 800,000 unaffiliated voters and the 261 New Yorkers registered with the party itself as of November 1. (gothamgazette.com)