INSTITUTE INDEX: An unprecedented wave of cash floods the South's midterms

The U.S. Senate race in Texas pitting incumbent Republican Ted Cruz (at left) against Democratic Rep. Beto O'Rourke (at right) is the most expensive ever. O'Rourke has raised more than any other Senate candidate in history, almost half of it in the form of small individual contributions of less than $200.

Total amount expected to be spent on the 2018 federal midterm elections, making them the most expensive in history: $5.2 billion

Previous spending record for a midterm election: $4.2 billion

Percent by which spending increased over the 2014 midterm election cycle, marking the most dramatic jump in at least two decades: 35

Amount by which Democratic candidates are expected to outspend Republicans this cycle: $300 million

Amount that outside groups unaffiliated with candidates or parties have spent so far at the federal level, with most of that going toward negative TV ads: $1.1 billion

Spending to date this cycle by secret-money groups that don't disclose their donors to the Federal Election Commission: $128 million

Decline that represents over the last midterm election, with more money instead being funneled through super PACs and other outside spending groups that only partially disclose donors: 28

Amount of secret money spent so far on the U.S. Senate races in Florida and Tennessee, which have been subject to the greatest such influence: $10 million

Rank of the 2018 U.S. Senate race in Texas among the highest-spending Senate races in history: 1

Record-breaking amount raised by Beto O'Rourke, the Texas Democratic congressman who's challenging Republican U.S. Sen. Ted Cruz: $61.8 million

With O'Rourke declining contributions from political action committees, percent of his take that came from small individual contributions of less than $200, the fourth-highest of any Senate candidate: more than 46

In the 30 U.S. House races CNN has identified as toss-ups this year, including contests in Florida, Kentucky, North Carolina, Virginia, and West Virginia, total amount contributed to Republican candidates: $90.7 million

To Democratic candidates: $166.8 million

If the Democrats win the U.S. House, rank of campaign finance reform among the top issues current House Minority Leader Nancy Pelosi (D-California) says she plans to tackle: 1

Chance that politics website 538.com gives the Democrats of winning the House: 6 in 7

Chance it gives them of winning the Senate, where current Majority Leader Mitch McConnell  (R-Kentucky) is a strong defender of big money in politics: 1 in 7

(Click on figure to go to source.)