Three-quarters of Republicans accept Donald Trump as their presidential nominee after an ugly primary season, a poll released Tuesday suggests. And that growing comfort level could be causing the presidential race to tighten up.  

According to the Public Policy Polling  survey, 72 percent of Republicans said they are comfortable with business mogul Donald Trump as their nominee for president.  

The same poll also found that 75 percent of Democrats felt the same way about former Secretary of State Hillary Clinton as their standard-bearer for the White House.  

Twenty-one percent of Republicans were not comfortable with Trump  as the nominee while 21 percent of Democrats were similarly uncomfortable with Clinton.  

Clinton remains ahead of Trump in head-to-head polling, 47 to 41 percent. Though her Democratic primary challenger, Sen. Bernie Sanders of Vermont leads Trump by a wider 11-point margin, 50 to 39 percent.  

As has been consistent throughout the election, Sanders overwhelmingly leads among young people. In a one-on-one matchup against Trump, Sanders leads the presumptive GOP nominee 70 to 14 percent among voters between the ages of 18 and 29. In contrast, Clinton holds a more modest 49 to 27 percent edge over Trump among voters in the same age group.  

Public Policy Polling conducted the survey of 1,222 registered voters between May 6 and 9. The margin of error was 3.2 percent.  

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