"Chris MurphyChristopher (Chris) Scott MurphyOvernight Cybersecurity: Senators want info on 'stingray' surveillance in DC | Bills to secure energy infrastructure advance | GOP lawmaker offers cyber deterrence bill Overnight Health Care: GOP pushes stiff work requirements for food stamps | Johnny Isakson opens up about family's tragic loss to opioids | Republicans refuse to back vulnerable Dem's opioids bill | Dems offer new public option plan Dems give muted praise to Pompeo-Kim meeting MORE is not happy that his lack of a work ethic has been exposed, but that’s the least of his worries," says an email from campaign manager Corry Bliss that goes along with the ad.

"Summarize" comes just a day after the release of a poll that showed McMahon leading Murphy by three percentage points. But a new poll flips that lead, with Murphy ahead of McMahon by four percentage points.

According to the poll from left-leaning Public Policy Polling, Murphy has 48 percent support to McMahon's 44 percent support. McMahon's favorability numbers are split pretty evenly in the poll, with slightly more -- 47 percent -- of voters rating her unfavorably than the 45 percent who have a favorable opinion of her, and only eight percent of voters are unsure about the candidate.

Murphy faces a similar gap in his favorability numbers, with 41 percent of voters viewing him unfavorably and 39 percent viewing him favorably -- but a full 20 percent of voters are still unsure about him.

The new poll also indicates Connecticut voters mostly have their minds made up, with only 8 percent of respondents saying they're still undecided in the race.

It was conducted among 881 voters from Aug. 22-23.