That $4 billion to be spent on TV in the 2016 election cycle is up 18% vs 2012, and could result in a windfall for station owners E.W. Scripps and Gray Television, according to a widely watched business estimate out this morning.

Wells Fargo Securities’ Marci Ryvicker tracks political spending more closely than just about anyone on Wall Street, making her a go-to source for analysis and projections regarding this increasingly important revenue source for media companies.

Top-Polling GOP Candidates Participate In First Republican Presidential DebateIn her first breakdown of the trends, she expects political groups and campaigns to raise $7.5 billion, up from about $6.5 billion in 2012 — the last election cycle that included a presidential race. Others have estimated that fundraising could reach $10 billion. But Ryvicker says she’s “reluctant” to count on such a big leap and figures $7.5 billion is “the right (and conservative) place to be right now.”

The rule of thumb is that about 80% of the cash goes to all forms of advertising. That would bring the 2016 number to $6 billion.

One challenge for election spending forecasters is figuring out how much likely will go to TV vs. digital platforms including Facebook, Google and iHeartRadio (the streaming service owned by the company formerly known as Clear Channel). They “are making a concerted effort to make as much political ad revenue as they can” in 2016, Ryvicker says.

But while digital’s share of the political ad pie should grow to 11% from 6% in 2012, it’s still relatively small at $642 million. And most of the share increase comes from dollars shifted from direct mail and newspapers.

Some digital evangelists believe its share could rise to 20%, but Ryvicker is unpersuaded. “While every candidate will likely have a digital presence, presence is free — don’t confuse ‘interactions’ with ‘ad-spend’,” she says.

Spot TV ads will remain “the preferred medium” for political commercials. Within TV, local outlets can expect $3.3 billion (up 18% vs 2012), network TV should see $108 million (up 4%), and cable will have $570 million (up 23%).

As for other media: Direct mail will have $720 million (down 23%), radio $300 million (up 11%), newspapers $60 million (down 23%), outdoor $60 million (up 46%), and other $240 million (up 32%).

The lion’s share of the cash will go to presidential swing states — led by Colorado, Florida, Ohio, and Virginia — as well as others with hotly contested local races. Senate campaigns in Florida, Nevada, and Wisconsin are currently considered toss-ups, while gubernatorial races in Louisiana, Montana, and West Virginia are seen as up for grabs.

To determine which TV companies will benefit most, Ryvicker looked at who has the most top-rated newscasts in the hotly contested states. She figures that Scripps (with its stations in Florida and Ohio) and Gray (in Virginia and Wisconsin) are “best positioned” overall, although network-owned stations from Disney’s ABC, Comcast’s NBC, and CBS should also do well.

Spending to promote issues, as opposed to candidates, “will be more or less the same” as in previous cycles.” Debates over foreign policy, the economy, immigration, health care, gun control and gay marriage “are not necessarily ‘new’ so spending on them has been continuous – in both election and non-election years. We don’t see why this would change very much.”

Republican Party logo GOPSome forecasters have wondered whether spending might be limited due to the Republican party’s effort to shorten its primary process. (The GOP convention next year will be in mid-July vs late August in 2012.) But Ryvicker says just the opposite. Once the crop of GOP candidates thins “the real fundraising and targeted advertising efforts are likely to begin. In fact, the anomaly right now is that the Republican candidates leading in the polls, i.e. Ben Carson and Donald Trump, are spending the least; and the lower polls for the remaining Republicans are making it difficult for them to raise more money. This should all change once the candidacy narrows.”