Democrats in highly competitive races skip the D.N.C

Senators Jon Tester of Montana and Sherrod Brown of Ohio, both locked in tight re-election battles, are working to keep other Democrats at arm’s length and avoid nationalizing their races.

Both will skip the convention, representatives for their campaigns said, to focus on their home turf.

Mr. Tester has not endorsed Ms. Harris’s presidential bid. His campaign said the senator was spending his August traveling the state and farming, and that he has not attended the convention in several campaign cycles. He is set to appear alongside members of the band Pearl Jam this week at a fund-raiser, a long-running relationship that stems from Mr. Tester’s high school friendship with one of the band’s members.

As for Mr. Brown, “we’ve been planning to be in Ohio for months and Sherrod is looking forward to hearing from Ohioans” at campaign stops this week, said Eliza Green, his spokeswoman.

Senator Jacky Rosen of Nevada, campaigning for re-election in a key swing state, is also skipping the convention. (Her campaign said she had done the same in 2016 and 2020.)

“Senator Rosen supports the Harris-Walz ticket and was glad to join them on the campaign trail in Las Vegas,” Joe Bush, a spokesman for Ms. Rosen, said in a statement.

“She is also focused on her own re-election and will be talking with Nevada voters during the week of the convention.”