ST. PAUL, Minn.  — Elizabeth Warren started the day with an apology, repeating her regrets for her past claims of Native American heritage. She ended it with a clear sign that Democrats aren’t holding the mistake against her — her largest crowd yet.

The arc of the day Monday captured the strengths and struggles of a presidential candidate who has made significant headway in a Democratic primary otherwise notable for its stagnation. The Massachusetts senator stands apart by having demonstrably improved her standing since her party’s White House field solidified in the spring while her competitors have risen and dipped in the national conversation and polls.

Some reasons for Warren’s rise are easy to spot. When she landed in Minnesota on Monday, her first stop in a state Republicans are eyeing to win next year, she brought a forward-looking message, a sophisticated ground operation, a folksy persona and an upbeat outlook.

“It looks like Minnesota is ready for some change in Washington!” Warren said to a crowd of several thousand, an enviable crowd size for any Democrat, including Minnesota Sen. Amy Klobuchar, a rival.

But Warren’s challenges were just as clear. She continues to have no easy response to President Donald Trump’s nickname for her — Pocahontas — an insult that, despite her efforts to move past her previous claims of tribal ancestry, reminds Democrats already nervous about her general-election viability of her biggest political unforced error. And the voters who filled a college green in St. Paul were overwhelmingly white, a reminder that she has not yet secured the diverse coalition she needs to win the nomination.

Warren on Tuesday took steps to expand her support with black voters, who largely favored Vice President Joe Biden in a poll released last week by the Pew Research Center, by unveiling a detailed criminal justice proposal. Underscoring the importance of filling a gap on her long list of plans for America’s ills, particularly for voters of color, Warren held a meeting with criminal justice reform proponents in Minneapolis.