The ad running in North Dakota charges that Rep. Rick Berg (R) has "gone Washington," citing what it characterizes as his votes to cut funding for higher education loans and scholarships while supporting tax cuts for the wealthy.

"We got more bills for a dimmer future," the ad charges.

Berg is running slightly ahead of challenger Heidi HeitkampMary (Heidi) Kathryn HeitkampOvernight Health Care: Supreme Court nomination reignites abortion fight in states | Trump urges Sessions to sue opioid makers | FDA approves first generic version of EpiPen Judge rules against Trump attempt to delay Obama water rule Vulnerable Dem Sen. Heitkamp hits opponent on ObamaCare repeal votes MORE (D) for retiring Sen. Kent Conrad's (D) seat, but Democrats believe this is one they can win, and have spent hundreds of thousands in the state in attacks on Berg. The charge that he's "gone Washington" is a common one, as Heitkamp has no Washington record to speak of and thus remains immune to those attacks.

In Connecticut, Majority PAC teamed up with Connecticut's Future PAC to launch an ad focusing on Republican Linda McMahon's prior statements on a "sunset" provision for legislation like Social Security, and contrasts that with her wealth.

The opening of the ad cites McMahon's millions and multiple homes, and then shifts to the candidate speaking at a Tea Party forum for Republican candidates, saying "I believe in sunset provisions when we pass this kind of legislation." The ad charges that McMahon's "sunset proposal would end Social Security."

"McMahon is set for life — we get sunset. That's just wrong," a narrator says.

From her actual remarks at the forum, however, it's unclear whether McMahon meant an expiration provision when she used the term "sunset." Though that's the commonly understood meaning of the term, the full quote indicates McMahon may have been using it differently.

"I believe in sunset provisions when we pass this kind of legislation, so that you take a look at it 10, 15 years down the road to make sure that it’s still going to fund itself," she actually said.

But the soundbite makes for a strong ad, and though Rep. Chris MurphyChristopher (Chris) Scott MurphyFormer Teacher of the Year wins Connecticut primary Live results: Wisconsin, Minnesota, Vermont, Connecticut hold primaries The Hill's Morning Report — Signs of trouble for Republicans in House special election MORE (D) is running slightly ahead of McMahon in most polls, the most recent independent poll in the race put her ahead by one point — indicating this is a race Democrats could lose, despite the blue lean of the state.