Virginia Republican Rep. Eric Cantor, the House Minority Whip and one of the GOP’s most potent fundraisers, used his leadership PAC last month to donate mostly to Republican candidates who are challenging Democratic incumbents in the 2010 election.

Cantor’s organization, known as Every Republican Is Crucial (ERIC) PAC, reported Monday that it donated $2,500 apiece to five GOP challengers about whom the congressman and other national party officials are bullish.

They are Andy Harris of Maryland, a state senator challenging Rep. Frank Kratovil Jr. in a rematch of their close 2008 race in the 1st District; Martha Roby of Alabama, a Montgomery city councilwoman who is taking on Rep. Bobby Bright in the 2nd District; Steve Pearce of New Mexico, a former House member who lost a Senate race in 2008 and is seeking to reclaim his old 2nd District seat, now held by Rep. Harry Teague; Steve Stivers of Ohio, who is waging a rematch campaign against Rep. Mary Jo Kilroy in the Columbus-area 15th District; and Van Tran of California, an assemblyman who is taking on Rep. Loretta Sanchez in the 47th District.