Until late 2007, no one expected him to come even close to winning in IA. Given his stronger than expected showing there, there was no reason for Huckabee to drop out in January 2007 2008.
If anything, it was Romney who prevented Huckabee from getting the nomination, not the other way around.
Back then he was actually doing better than Romney, so the only "people" who "kept telling him" to drop out were hardcore Romney supporters who became bitter toward Huckabee because he is a genuine conservative (as opposed to Romney) and was doing better than him.
Iowa - 1/3/081. Huckabee (17 delegates)
2. Romney (12 delegates)
3. McCain (3 delegates)
3. Thompson (3 delegates)
Wyoming - 1/5/081. Romney (8 )
2. Thompson (3)
3. Hunter (1)
New Hampshire - 1/8/081. McCain (7)
2. Romney (4)
3. Huckabee (1)
Michigan - 1/15/081. Romney (24)
2. McCain (5)
3. Huckabee (1)
Nevada - 1/19/081. Romney (17)
2. Paul (4)
3. McCain (4)
South Carolina - 1/19/081. McCain (19)
2. Huckabee (5)
3. Thompson (0)
Florida - 1/29/081. McCain (57)
2. Romney
3. Giuliani
Maine - 2/1-3/081. Romney (18)
2. McCain
3. Paul
Super Tuesday - 2/5/081. McCain (608)
2. Romney (197)
3. Huckabee (160)
Total Delegates through 2/5/081. McCain (703)
2. Romney (280)
3. Huckabee (187)
Romney drops out on 2/7/08.
The only time Huckabee every actually led, was right after Iowa.
What do you consider to be "economic credentials"?