From The Collaborative International Dictionary of English v.0.48 :
cross-file \cross-file\ v. i. & t.
to register as a candidate for more than one political party
in the same election.
[WordNet 1.5]
From WordNet (r) 3.0 (2006) :
cross-file
v 1: have one's name listed as a candidate for several parties
[syn: cross-file, register]