All five are Republicans, The Hill newspaper reported.

Craig Williams, running against Joe Sestak, D-Pa., said drilling in the Arctic National Wildlife Refuge would "provide a bridge to tomorrow when we can more heavily rely on renewable energy resources such as hydro-electric, solar and wind power."

President Bush has supported the idea of exploring the area's potential for drilling. But, presumptive presidential candidates Barack Obama, D-Ill., and John McCain, R-Ariz., both oppose the idea, the Hill reported.

Accompanying Williams on the July trip are Chris Lien, running for a seat in South Dakota against Rep. Stephanie Herseth Sandlin; Paul Stark, who is challenging Rep. Ron Kind, D-Wis.; Luke Puckett, running against Joe Donnelly, D-Ind., and Mike Sodrel, who is challenging Baron Hill, D-Ind.