Young people traditionally stay home in droves on election day, but they are voting in much higher numbers in battleground state primaries this year, according to a new report.

Why it matters: In the state-by-state analysis, the Democratic data firm TargetSmart said young people 18-29 have the potential to decide control of Congress and affect competitive races for governor in key states on Nov. 6.

The report compared youth turnout in this year's primaries with the last midterms in 2014. Among the findings:

• In North Dakota, where Sen. Heidi Heitkamp is one of the most vulnerable Democrats seeking re-election, turnout jumped to 11.7% of registered youth voters, from 4.8% previously.
• California, a crucial state with a number of Republican-held “toss-up” seats this cycle, had a 9.3% increase.
• Oklahoma turnout surged by almost 18%.
• Montana turnout jumped 6%.