Minnesota U.S. Sen. Amy Klobuchar has never won any of her three previous Senate races by fewer than 20 points. So it’s at least notable that our latest KSTP/SurveyUSA poll shows her with leads of 14 and 13 points in hypothetical matchups with two potential Republican challengers.

In our survey conducted June 12-16, Klobuchar leads Republican-endorsed candidate Royce White 49% to 35% with 12% undecided. Joe Fraser, who is challenging White in a primary in August, trails Klobuchar 49% to 36% with 11% undecided.

RELATED: KSTP/SurveyUSA poll: Klobuchar positioned to win reelection, but could be closer than usual

“Royce White and Joe Fraser have almost identical numbers against Amy Klobuchar and they’re not well known by most people in Minnesota,” says Carleton College political analyst Steven Schier, noting that the numbers are remarkably similar for the two Republicans. “You’ve got the base vote of the Republican Party reflected in this survey. The problem for both Royce White and Joe Fraser is convincing those people who are not part of the Republican base to vote for them and they may not have the record or the resources to do that.”

White and Fraser both get about 80% support among Republicans, but Klobuchar has big leads among independents. Among those voters, she leads Fraser by 21 points and holds a wider lead of 26 points over White.

The poll also seems to reflect that Republican respondents who support White don’t seem troubled by his controversial past, including civil court actions, unpaid business debts, allegations of antisemitism and domestic abuse and campaign finance complaints.

Schier says that record would come under more scrutiny in a general election if he wins the primary.

“If Royce White gets to the general election, the public will gradually know more about him,” Schier says. “He’ll have to do a lot of explaining and he’ll probably be consistently on the defensive in a race in which he is the underdog.”

SurveyUSA interviewed 800 adults from the state of Minnesota June 12-16. Of the adults, 703 were identified as being registered to vote; of the registered voters, 626 were determined by SurveyUSA to be likely to vote in the November general election.

This research was conducted online, using a nonprobability sample of online adult panelists chosen randomly by Lucid Holdings, LLC of New Orleans. The combined pool of survey respondents was weighted to U.S. Census ACS targets for gender, age, race, education and home ownership.

The poll includes 41% of respondents who identify themselves as Democrats, 36% as Republican and 20% as independents.

View the full survey results below: