Republican Senate candidate and beer magnate Peter Coors (search) is coming under attack in a new TV ad for supporting the lowering of the drinking age from 21 to 18.

The ad, from a group supporting Coors' GOP primary rival Bob Schaffer (search), features images of Coors Light cans and young people chugging beer.

"Beer executive Pete Coors says we should lower the drinking age so teenagers can drink," says the commercial, which will be released in the next few days by Colorado Conservative Voters. "Makes you wonder what else we should know about Pete Coors. Oh, Pete!"

An earlier ad by the same group criticized Coors for his company's gay-friendly policies.

Coors reiterated his support for a lower drinking age during a debate with Schaffer last month, saying that young people drink anyway and the government has made them criminals. Before 1987, Coloradans 18 to 21 could legally drink beer with a 3.2 percent alcohol content.

Coors has run a television ad criticizing Schaffer for trips he took as a congressman.

The two Republicans are battling to succeed retiring GOP Sen. Ben Nighthorse Campbell. Attorney General Ken Salazar and educator Mike Miles are seeking the Democratic nomination in the Aug. 10 primaries.