Total campaign ad spending for U.S. Senate, U.S. House, gubernatorial and other races in the U.S. midterm elections has surged past $2.1 billion, according to the latest Ad Age Campaign Ad Scorecard analysis.

Campaign Ad Scorecard is part of Ad Age’s Campaign Trail coverage, a project of Ad Age Datacenter, led by Director of Data Management Kevin Brown in partnership with Kantar/CMAG.

An executive summary of—and essential context for—the charts you see below:

• The $2.1 billion campaign ad tally includes TV, radio and tracked digital advertising from Dec. 28, 2021, through Election Day as of July 5, 2022. Our tallies include spending by the candidates’ campaigns as well as the political action committees supporting them.

• U.S. Senate campaign ad spending accounts for $878 million of the total, with Republicans ($460 million) outspending Democrats ($405 million). (The remaining $13 million in the tally covers independent candidates and issue-advocacy ads related to the Senate race.)

• U.S. House race campaign ad spending accounts for $485 million of the total, with Republicans ($265 million) outspending Democrats ($220 million) and independents/issue-advocacy (effectively $0).

• Gubernatorial race campaign ad spending accounts for $517 million of the total, with Republicans ($289 million) outspending Democrats ($224 million) and independents/issue-advocacy ($3 million).

• The three most expensive U.S. Senate races in terms of ad spending during our tracked period are those in Georgia ($155 million), Pennsylvania ($143 million) and Arizona ($119 million).

• In Arizona, Democrats ($72 million) are outspending Republicans ($45 milion) on campaign ad spending in the U.S. Senate race, which pits incumbent Sen. Mark Kelly, a former astronaut and the presumptive Democratic nominee, against a Republican candidate to be determined in the Aug. 2 primary. Donald Trump has endorsed Blake Masters, a venture capitalist backed by Peter Thiel, the billionaire technologist and fellow venture capitalist; Masters is the president of the Thiel Foundation, a private grant-making organization.

• Helping to drive up ad spending in Arizona: an influx of dollars from political action committees. Of the five biggest spenders on the Arizona U.S. senate race, four are PACs (see chart, below), led by the Senate Majority PAC, a pro-Democrat group that has burned through $27 million in ad spending during our measurement window.

• Among the individual Arizona campaigns, Mark Kelly’s is the top spender on advertising so far ($21 million), followed by those of Republican challengers Masters ($1 million) and Jim Lamon ($7 million).

• Though Lamon is trailing Masters in the polls, he is, like Masters, very well-funded. “To focus on his commitment for AZ US Senate,” the Lamon campaign’s official website notes on its about-the-candidate page, “Jim sold his company at the end of 2021.” Interestingly, though the name of the company, Depcom, is mentioned, the nature of the business—Depcom is a solar power company—is not mentioned, though the campaign makes sure to point out that “Prior to founding Depcom, Jim worked for 20 years in the coal and gas-fired power plant industry. Jim knows what it takes to power America.”

Depcom Power was acquired for an undisclosed sum last November by Koch Engineered Solutions, a unit of Wichita, Kansas-based privately held multinational conglomerate Koch Industries. (Charles Koch, the billionaire chairman and CEO of Koch Industries, is a longstanding major donor to conservative political campaigns and think tanks.) Last winter, Politico reported that “Jim Lamon told a gathering of GOP women [that] he planned to put a staggering $50 million of his own money into his Senate race.”

• In Georgia, Democrats ($92 million) are outspending Republicans ($59 million) on advertising. Georgia, as we’ve previously noted, is the subject of intense attention—and national-level fundraising—from both major parties, given the pivotal role the Peach State played in the 2020 presidential election. Also raising the temperature there: the news last week that a Georgia grand jury has issued subpoenas for multiple Trump advisers in a criminal investigation into election meddling.

• Complicating matters in Georgia: Incumbent U.S. Sen. Raphael Warnock (D) has been in office only since January 2021; he won a special election for the seat, which was previously held by Kelly Loeffler (R). Warnock will face off against former football player Herschel Walker, who won the Republican nomination and has been endorsed by Donald Trump. According to a Quinnipiac University poll of Georgia registered voters conducted in late June, Warnock leads 54% to 44% over Walker, who has lately been the subject of a slew of unfavorable headlines related to a “secret kids” scandal (e.g., “Georgia Senate hopeful Herschel Walker acknowledges he has 4 children, insists he wasn’t ‘hiding’ them,” from ABC News).

• In Pennsylvania, Republicans ($84 million) are outspending Democrats ($59 million) on U.S. Senate campaign advertising. There is no incumbent in the Keystone State—U.S. Sen. Pat Toomey (R) announced in October 2020 that he wouldn’t seek reelection—which led to a contentious primary race between two well-financed Republican candidates: former TV doctor Mehmet Oz and former hedge fund manager Dave McCormick. Oz won the Republican primary in a squeaker, and John Fetterman, the lieutenant governor of Pennsylvania, won the Democratic nomination. As of this writing, FiveThirtyEight calls the race a “toss-up,” with Oz winning 48% of the time and Fetterman 52% of the time in its election-simulation model.

• Complicating matters in Pennsylvania: Fetterman had a stroke on May 13—just four days before the primary. Per a June Insider headline: “John Fetterman’s cardiologist says he didn’t see a doctor for 5 years until he suffered a stroke caused by heart disease.”

Now Fetterman has to see Oz—a former cardiothoracic surgeon—every day.