Updated

John Kerry keeps the momentum going this evening with a win in the Wisconsin Democratic primary; however, the race was much tighter than expected with a late surge from North Carolina's John Edwards (search) that helped him come in a strong second.

A 58 percent majority of today’s voters said they decided their vote within the last week and Edwards won an impressive 45 percent of these "late deciders" besting Kerry by 15 percentage points. Conversely, Kerry won 52 percent of "early deciders" or those voters who decided in the last month or before that.

As has been the case in almost all primaries so far this season, the economy topped the list of issues (chosen by 41 percent), with health care (19 percent) and the war in Iraq (17 percent) coming in far behind. Edwards beat Kerry (46 percent to 35 percent) among those who said the economy topped the list, while Kerry had double-digit victories with health care voters as well as those who said Iraq was most important.

With Edwards’ message about "two Americas," it might be expected that he would do well among lower income groups — however just the opposite was true today.  Kerry bests Edwards by 11 percentage points among voters with family income below $50,000 (about half of all Wisconsin primary voters), while the vote is evenly divided among those with a family income over $50,000.

On the issue of trade, a key issue for Edwards, almost three-quarters of voters said U.S. trade with other countries takes more jobs from Wisconsin than it creates, and these voters split their support almost evenly (Edwards 36 percent and Kerry 39 percent).

The personal strengths of the candidates were clearly evident today, as Kerry won 69 percent of voters who said defeating Bush in November was the most important candidate quality and Edwards won 47 percent of those who choose "care about people like me" and 57 percent of those who picked "has a positive message" as the top quality.

Overall, the top candidate quality was "stands up for what he believes" and, although he came in third in today’s primary, former Vermont Gov. Howard Dean (search) won this group (32 percent) followed by Edwards (28 percent) and Kerry (24 percent).

One reason the race was so close was Wisconsin has an open primary (no party registration) and over a third of voters were independents or Republicans — pluralities of both groups voted for Edwards, while Kerry captured almost half of self-described Democrats (62 percent overall).

About one in five voters today were veterans, and they gave only a slight edge to their fellow vet (41 percent for Kerry to 36 percent for Edwards).

The vote was about even among men (35 percent Edwards and 36 percent Kerry), while women gave a six-percentage point edge to Kerry. In addition, whites divide their vote but black voters were much more likely to support Kerry.

Finally, Kerry had a slight edge over Edwards (47 percent to 41 percent) among voters who said they had previously been Dean supporters — about a quarter of voters overall.

This exit poll was conducted for Fox News by Edison/Mitofsky. The results are based on interviews with 2,277 Democratic primary voters in Wisconsin.

Click below for more detailed results.

• Wisconsin, pdf