Hillary Clinton’s Lead Over Donald Trump Narrows

Republican support boosts presumptive nominee’s chances against the former secretary of state in new poll.

Republicans have rallied behind Donald Trump in the weeks since he effectively clinched his party’s presidential nomination, helping him narrow Democrat Hillary Clinton’s once double-digit lead to just 3 percentage points, a new Wall Street Journal/NBC News poll shows.

Mrs. Clinton leads the New York businessman, 46% to 43%, in a test matchup between the two likely nominees, the poll finds. That represents a much tighter margin than her 11-percentage-point lead in April and marks the first time in Journal/NBC News polling this year that her support dropped below 50% in a contest with Mr. Trump.

The poll has a margin of error of plus or minus 3.1 percentage points.

The main reason Mr. Trump has eaten into Mrs. Clinton’s lead is he enjoys much wider support from GOP voters after his decisive win in the Indiana primary earlier this month, a victory that prompted his two remaining rivals to exit the race. The presumptive GOP nominee has also opened a modest lead among self-described independent voters.

In the matchup against Mrs. Clinton, Republican support for Mr. Trump jumped to 86% from 72% in mid-April, while the share of GOP voters who said they would support Mrs. Clinton fell to 6% from 13% a month earlier. Democrats’ support for Mrs. Clinton, meanwhile, remains largely unchanged.

The poll shows the race at this early point is virtually a statistical dead heat. That is in keeping with other polling done since Mr. Trump vanquished his remaining Republican primary foes.

To some extent the polling reflects for Mr. Trump the boost that naturally comes when a candidate prevails in a primary race and stops coming under direct attack by his primary rivals, a luxury Mrs. Clinton doesn’t have and may not until her party’s July convention. Still, the results, though early, are troubling for the Democratic team because they may suggest how much damage the bruising primary fight has done to her, which could linger after the battle ends.

Perhaps the best news in the survey for Mr. Trump is that he outpaces Mrs. Clinton, 46% to 43%, in the 12 most competitive presidential battleground states—states that President Barack Obama won by 1.5 percentage points in 2012. He does particularly well in the South and Midwest.

But national polls such as this don’t fully capture the two candidates’ standing in these 12 states because they aggregate the numbers, which can vary dramatically from one state to the next.

The share of Democratic primary voters who view Mrs. Clinton favorably dropped from 84% last June to 65% in the latest poll, while the share who view her negatively jumped from 7% to 21%.

A chief task for any nominee is to unify his or her party ahead of the general election. In the new survey, some 83% of Democrats said they prefer Mrs. Clinton over Mr. Trump, down slightly from 87% in April.

A remarkable 1-in-10 voters say they wouldn’t vote for either Mrs. Clinton or Mr. Trump, a reflection of both candidates’ unusually bad public images, and 47% say they would consider an independent or third-party candidate in the fall, up from 40% in the spring of 2012 and 38% in the winter of 2008. Half of voters in the current poll say they wouldn’t consider an independent or third-party candidate.

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