Massachusetts Sen. John Kerry clinched a narrow victory in Tuesday’s Wisconsin primary election, with North Carolina Sen. John Edwards nabbing a surprisingly close second-place finish.

With all precincts reporting, Kerry sealed his 15th state contest win with 39.7 percent of the vote. Edwards garnered 34.3 percent, and former Vermont Gov. Howard Dean trailed far behind with 18.3 percent.

At the American Serb Hall in Milwaukee, Wis., Edwards told a cheering supporters that his second-place finish demonstrated he could challenge Kerry for the nomination.

“Today the voters of Wisconsin sent a clear message: Objects in your mirror may be closer than they appear,” said the freshman senator who had trailed Kerry by almost 27 percentage points in a poll of 600 likely voters released Monday. “We will continue this campaign to build one America.”

But Kerry made no mention of the closeness of the race in his Tuesday night victory speech.

“I want to thank the state of Wisconsin for moving this cause and this campaign forward tonight, here in this great state,” said Kerry, calling on voters to make the United States “a land of opportunity not just for some, but for all.”

The strong showing by Edwards, who was endorsed Monday by the Milwaukee Journal Sentinel, breathed new life into his campaign. He told supporters that Tuesday’s results will turn the contest into a two-man race as the March 2 “Super Tuesday” of 10 primaries approaches.

“We’ll go full-throttle to the next group of states,” Edwards said.

But Dean, who has failed to win in any of the 17 states that have held primaries or caucuses so far, told supporters Tuesday night at a rally in Madison, Wis., to “never give up.”

“You all make me so happy, I could just scream,” Dean told a cheering crowd — making reference to his raucous, post-caucus speech in Iowa. “You have already written the platform of this party for the election.”

Dean had said in recent weeks that a loss in Wisconsin would force him to end his campaign, but he did not drop out Tuesday.

Wilmette resident Steven Birenberg, who has campaigned for Dean in Iowa and several other states, said he was disappointed with Dean’s decline — blaming it on voters’ preference for a less aggressive candidate.

“It’s disappointing having invested so much time and effort,” Birenberg said. “But I think the Dean campaign has been critical in improving the prospects that the Democrats have in winning the White House in November. He taught the other Democrats in the party that it’s time to stand up to the Republicans.”

Before the results came in, Mike McCurry, a former press secretary in the Clinton administration who spoke at Northwestern on Tuesday, said a Kerry win in Wisconsin likely would solidify Kerry’s status as the front-runner for the Democratic nomination, whereas a strong showing for Edwards would revitalize and give more legitimacy to his campaign.

“John Kerry is well on his way to becoming the Democratic nominee,” said McCurry, who added that Edwards’ presence in the race could make Kerry a stronger candidate. “John Edwards might just have gotten another lease on life.”

Recent graduate Joe Bubman, a Kerry campaign volunteer who spent Tuesday night at a polling station at the University of Wisconsin-Madison, said it’s only a matter of time before Kerry secures the party’s nomination.

“It is very exciting, because Wisconsin is a stand-alone primary, with no other states competing on the same day, ” said Bubman, Weinberg ’03, who also worked for Kerry’s campaign in Iowa and Missouri. “Wisconsin has been billed as a very critical state, simply because Dean came out and said initially that if he didn’t do well, he would drop out.”

The attention given to Wisconsin, which has 72 delegates, makes Edwards’ strong second-place finish more significant, supporters said.

Weinberg junior Sam Hong, coordinator of Northwestern Students for Edwards, said his candidate is now Kerry’s main challenger.

“It’s pretty much a two-man race now,” said Hong, a former Daily staffer. “I really think Edwards has proved today that Kerry isn’t just going to win this over.”

The Daily’s Amy Hamblin and The Associated Press contributed to this report.