Unemployment rates rose in 44 US states in July, the most states to show a monthly increase in more than three years and a reflection of weak hiring across the US.
The Labor Department says unemployment rates fell in only two states and were unchanged in four.
Unemployment rates rose in nine states that are considered battlegrounds in the presidential election.
That trend, if it continued, could pose a threat to President Barack Obama's re-election bid in less than three months.
Nationwide, hiring improved in July after three months of tepid hiring.
But the national unemployment rate ticked up to 8.3% from 8.2%.
Monthly job gains have averaged 150,000 this year. That is barely enough to accommodate population growth. As a result, the unemployment rate is the same as when the year began.
Still, 31 states gained jobs in July, while 19 lost them. Unemployment rates can rise in a state even when more jobs are created if more people start looking for jobs. People who are out of work are counted as unemployed only if they are looking for a job.
In the most closely contested states in the presidential race, unemployment has fallen over the past year. But it has started to tick up in recent months. In Nevada, the rate rose to 12% in July from 11.6%. That is the highest rate in the nation, though it is still much lower than a year ago, when it was 13.8%.
In Florida, the rate increased to 8.8% from 8.6% in June. Unemployment also increased in Virginia, North Carolina, Iowa, Pennsylvania, Michigan, Colorado, Wisconsin and New Hampshire.
The rate was unchanged at 7.2% in Ohio, the only swing state that didn't suffer an increase. Still, that rate is down sharply from 8.9% a year ago.
The US economy has not been growing fast enough to generate more hiring.
It expanded at an annual rate of only 1.5% in the April-June quarter, down from 2% in the first quarter and 4.1% in the final three months of last year.
