As late as last week, Scott Walker had the lead among Republican caucus-goers in Iowa. But two new polls, both taken after the GOP debate last week, show that Donald Trump is now leading in Iowa. Was it Walker's rather lackluster performance in the debate that caused this, or did Iowans like the show Trump put on? Maybe it's a bit of both. Either way, this is not good for Walker -- because Iowa is in his back yard, and he should be able to do very well there.
The Suffolk University Poll was done between August 7th and 10th of a random sample of 500 likely GOP caucus attendees, and has a margin of error of 4.4 points.
The Public Policy Polling survey was done between August 7th and 9th of a random sample of 619 likely GOP caucus attendees, and has a margin of error of 3.9 points.
Note that Trump's lead over Walker exceeds the margin of error in both polls.