The decision to increase the buy to $75,000 — which a spokesman for the PAC said is significant in the Omaha-area district — comes as a recent poll showed Democrat John Ewing halving Terry's lead.

That poll, from the Omaha World-Herald, still put Terry ahead of Ewing by 6 percentage points among registered voters, 48 percent to 42 percent support — down from a 12-percentage-point lead for Terry in September.

Terry has still substantially outraised Ewing, with $1.9 million in fundraising over the cycle to Ewing's $491,000, which explains why Ewing has been slow to get on the air with his own ads.

But House Majority PAC's buy could level that playing field and potentially give Ewing a chance for a surge in the final stretch.