NASHVILLE (BP)—Republican Mike Huckabee has built a double-digit lead in Iowa, while Democrats Hillary Clinton and Barack Obama are locked in a tight contest in that state leading up to the Jan. 3 caucus, according to the latest polls.

RealClearPolitics.com's average of the last four Iowa polls has Huckabee at 34.0 percent, Mitt Romney at 23.3, Rudy Giuliani at 9.8, Thompson at 9.5 and John McCain at 5.8. Among Democrats in the polling average, Obama leads with 29.8 percent, followed by Clinton (26.3) and John Edwards (23.0)

In New Hampshire, Real ClearPolitics.com's average of the last four polls has Romney leading with 32.0 percent, trailed by McCain (18.5), Giuliani (16.5), Huckabee (11.0) and Ron Paul (7.0). On the Democratic side, Clinton is at 31.5 percent, followed by Obama (28.5) and Edwards (16.3).

Nationally, a six-poll average has Giuliani in first among Republicans with 22.7 percent, trailed by Huckabee (20.7), Romney (15.3), McCain (12.3) and Thompson (10.2). Among Democrats, Clinton leads Obama 43.8-25.3. Edwards is third at 12.2.