LA Times has
polled Iowa (PDF). MoE 4%. No trend lines.
Of likely Caucus-goers (including leaners):
Dean 30
Gephardt 23
Kerry 18
Edwards 11
Don't know 9
Clark 4
Kucinich 3
Lieberman 2
Braun 0
Sharpton 0
Second choice candidates:
Edwards 22
Kerry 21
Dean 20
Gephardt 18
Braun 3
Clark 3
Kucinich 2
Lieberman 2
Interestingly, the second choice of Dean, Kerry, Edwards and Gephardt split almost evenly three ways to the other three guys. Of Kerry supporters, Dean was the second choice of 32 percent. Of Dean supporters, Edwards was the second choice of 27, Kerry 25.
Gephardt seems to have the most solid support, with 68 percent saying they are fully committed to their guy. Dean is at 61, Edwards 58, and Kerry 51.