Democratic candidate Dan Maffei leads 46-38 over incumbent Ann Marie Beurkle in a new poll out by Grove Insight. The poll was sponsored by the Democratic Congressional Campaign Committee. The last publicly available poll by Siena had the race tied at 43-43. Both polls have Green party candidate Ursula Rozum at 7%. The poll's margin of error is +/- 4.9 percentage points.
The news here is among the available polls, Siena's appears to be the outlier in this race. Most polling data in this district shows Generic D over generic R at about 46-40, which is consistent with the Grove Insight poll, as well as all the non-Siena head to head match-ups. Grove Insight's last poll had Maffei leading Beurkle 48-42.
The (not really) bad news is this is a DCCC-sponsored poll. Siena's is the only independent poll available for this race so far this cycle. According to that poll, Maffei has some advantages that do not seem to translate into their head-to-head numbers. Maffei's favorables are 49/37, while Beurkle stands at 44/44. Obama also leads the district over Mitt Romney 55 to 36.
Edit to add link to the Siena college poll.
Another edit to add link to Maffei for Congress