WASHINGTON — Senate Commerce Committee chairman John McCain (R-Ariz.) accused the House Commerce Committee of creating a “loophole” that would allow broadcasters to hoard valuable TV spectrum until well into the next century.McCain is still working on legislation, which he will introduce Tuesday, that will close that loophole, an aide to the senator said Friday. The House Commerce Committee voted last week to allow TV stations to hold on to both their current channel and the digital channel they will soon receive until 95% of their local market makes the transition to digital TV. The measure was opposed by Democrats who, like McCain, believe that digital TV will not hit the 95% penetration level until well beyond 2006. Under the current Federal Communications Commission plan, broadcasters would give back their current channel in 2006 so it can be auctioned. Both the House and Senate Commerce Committees must come up with proposals to raise more than $20 billion from spectrum auctions. McCain has been a strong supporter of the FCC plan, which congressional bean-counters say would raise $5.4 billion to offset the budget deficit. McCain also opposes a proposal by the Clinton administration to charge an annual fee for the use of spectrum. Variety incorrectly reported last week that McCain supported the proposed fee.