From Longman Dictionary of Contemporary Englishrunning mateˈrunning mate noun [countable usually singular] PGPVOTE/ELECTthe person chosen by someone who is trying to become president, leader etc to help win an election, and be the second most important political person if they are elected
Examples from the Corpus
running mate• Don Nickles, R-Okla., as a running mate.• He has not yet found a running mate, although he has approached several minor political figures.• Kennedy chose Johnson as his running mate in the 1960 presidential election.• Who is his running mate for vice-president? 16.• Bob Dole would love to make Colin Powell his running mate.• Perot threw his last running mate, retired Adm.• Indeed she is sometimes spoken of as a possible running mate in November.• Within moments of Bush's certification, Gore's running mate, Sen. 