A list of the House races for which Democrats have asked broadcasters and cable companies to reserve $44 million in ad time provides a revealing look at the shape of the midterm election landscape this fall.

  • The Democratic Congressional Campaign Committee plans to spend money in some of the bluest states on the map — places like Massachusetts, Illinois and California.
Take the 6th Congressional District of Massachusetts, for example. The DCCC has allocated about $1.4 million to help Rep. John Tierney hang onto that seat. The nine-term congressman, whose district is located northeast of Boston, has been dogged by ethics issues; he narrowly won re-election in 2012 with 48.3 percent of the vote in a three-way race. It's a Democratic-oriented district, but more politically marginal than the typical Massachusetts district. Democrats are also spending in California's 26th Congressional District, represented by first-term Rep. Julia Brownley. The DCCC has allocated $950,000 for cable TV campaign ads on Brownley's behalf from late September to Election Day. Brownley beat her Republican rival by just 5.4 percentage points, but ran behind Obama's winning performance there. That has emboldened Republicans who see her seat as a potential pickup, despite the Democratic voter registration edge.

  • Democrats have no choice but to spend big in red districts where Democrats currently and somewhat improbably hold seats.
Take Minnesota's 7th Congressional District, represented by 12-termer Rep. Collin Peterson. One of the few remaining moderate Blue Dog Democrats, Peterson won 60.4 percent of the vote in 2012 — in a district where Mitt Romney won comfortably by 10 percentage points. If this turns out to be a really bad year for Democrats, Peterson could be in serious trouble. So the DCCC plans to spend $1.5. million on TV advertising to hold the mostly rural district, which runs nearly the entire western length of the state. Democratic Rep. John Barrow, who represents Georgia's 12th Congressional District — another seat where Romney won by a comfortable 11-point margin — is a similar case. He's a perennial GOP target because of the conservative orientation of his district; the DCCC plans to plow nearly $1.2 million into TV ads.

  • House Democrats are also targeting some Republicans whose defeat would give many progressives more satisfaction than just picking up the seat.
Tea Party favorites like Michigan's Tim Walberg and Justin Amash, and Rep. Steve King, an Iowa Republican who represents the state's 4th Congressional District, are in this category. One of the most caustic critics of an immigration overhaul, King's defeat would probably go a long way to consoling progressives, even if Democrats fail to regain House control — which seems all but certain. So the DCCC plans to spend $670,000 on TV ads in their effort to defeat him. King, in his sixth term, won his last election by 8 points, however, beating Christie Vilsack, wife of Obama's agriculture secretary and former Iowa Gov. Tom Vilsack.Copyright 2016 NPR. To see more, visit http://www.npr.org/.