Republican presidential candidate John McCain will miss another event for conservative activists this month while he's on a trip to Iraq, but he says he's not sidestepping invitations to appear before right-leaning groups.

The Arizona senator will not attend the Club for Growth's annual winter conference in Palm Beach, Fla., that starts March 31, an event that will feature speeches by Republican candidates Rudy Giuliani, Mitt Romney and Sam Brownback.

"I've had this trip to Iraq scheduled for a very long period of time," McCain told reporters Tuesday outside a $1,000-a-plate fundraiser. "And I think it's more important, as the ranking member of the Senate Armed Services Committee, to visit regularly Iraq, particularly during this very critical time as we go through this new strategy."

McCain was the only leading Republican candidate to skip the Conservative Political Action Conference earlier this month, and the mention of his name there drew occasional boos. The senator also bypassed a retreat for members of the Heritage Foundation and a conservative summit hosted by the National Review Institute.

Club for Growth President Pat Toomey said he took McCain's explanation at "face value," but added that with McCain failing to show at a string of conservative-sponsored events "it starts to look like a pattern emerging."

In another sign of friction, the Club for Growth issued a statement Monday that said McCain's record on economic issues was "tainted by a marked antipathy towards the free market and individual freedom."

Campaign spokesman Matt David said McCain "is the only leading Republican candidate with a 24-year record as a fiscal conservative