CNN

Giuliani and McCain have both taken a dip in the latest Iowa poll following their decision to skip the straw poll.

WASHINGTON (CNN) - It looks like Iowa Republicans may not like the decision by Sen. John McCain and former New York City Mayor Rudy Giuliani to skip to straw poll in Ames this August, with the Arizona Republican feeling their anger the most, a recent Mason Dixon poll indicates.

Previous polling by other firms in Iowa have shown both men with support as high as the mid-20's. But the current Mason-Dixon poll shows Giuliani with just 15 percent - good enough for a statistical tie for second-place - and McCain dropping all the way to single digits at 6 percent - essentially tied for fourth place with former Arkansas Gov. Mike Huckabee, who polled 7 percent, and Kansas Sen. Sam Brownback, who polled 6 percent.

Former Massachusetts Gov. Mitt Romney leads the poll with 25 percent, followed by former Tennessee Sen. Fred Thompson, who registered 17 percent. Thompson has yet to officially jump in the White House race.

27 percent of those polled reported they were undecided.

Iowa and New Hampshire are two states in which voters have traditionally been very touchy to any presumed slights, and it's not out of the question that some of them interpreted the decision to bypass the straw poll as an insult to the Hawkeye State.

And since McCain sat out the Iowa caucuses entirely in 2000, his decision on the straw poll might have sounded particularly harsh to many.

Mitt Romney has spent significant time and money in the state. He has steadily run television ads there since February.

This is not the first poll that has shown Romney leading the field in Iowa, and that, combined with his first-place showing in recent New Hampshire polls, indicates that his single-digit showing in national polls may not reflect his true strength in the GOP field.

It's important to note, however, that finding Iowa caucus-goers is a needle-in-a-haystack problem, so early Hawkeye state polls may not necessarily be a good indication of the final caucus results.

The poll conducted form June 13-16, interviewed 400 likely caucus goers, and carries a margin of error of plus or minus 5 percent.

– CNN Polling Director Keating Holland