Washington ? Narrowly defeated in his bid for a fourth term, Montana Sen. Conrad Burns turned his anger on the National Republican Senatorial Committee and commercials it had run months before the election.

“The ads hurt me more than they helped. I wouldn’t have spent the money,” he said, his comments characteristic of the season of second-guessing now unfolding among Republicans.

President Bush’s low approval ratings, the unpopular war on Iraq, voter concern about corruption and Democratic fundraising all figured in the GOP loss of Senate control in last month’s elections. But among Republicans, long-hidden tensions are spilling into view, with numerous critics venting their anger at the GOP Senate campaign committee headed by North Carolina Sen. Elizabeth Dole.

In recent interviews, officials said Senate Majority Leader Bill Frist, R-Tenn., as well as Ken Mehlman, the party chairman, set up outside checks on the committee at critical points in the campaign.

As early as last summer, Mehlman signaled he lacked full confidence in Dole’s committee. In an unprecedented move, he set up an independent entity to control more than $12 million that the Republican National Committee spent for television advertising in Ohio, Tennessee and Missouri.