From OpenSecrets.org:

This year’s midterm election cycle is slated to become the first and only member of the $5 billion club. The Center for Responsive Politics projects that more than $5 billion will be spent during the 2018 election, making it by far the costliest congressional election cycle in U.S. history.

“We expected to see the numbers climb, as they typically do, but the astonishing spike in campaign donations is a solid indicator of the intensity driving this year’s campaigns,” said Sheila Krumholz, executive director of the Center for Responsive Politics.

The 2016 election was the most expensive congressional election, with just over $4 billion spent for House and Senate candidates in total. Only two congressional election cycles have surpassed the $4 billion mark — 2016 and 2010 — when adjusted for inflation.

More than $3.7 billion has already been spent on the 2018 election, including money spent by candidates, parties, committees, PACs and outside groups, for the purpose of the election.

Democratic candidates have a huge lead in spending over Republicans, having shelled out more than $1 billion to Republican candidates’ $720 million. Democrats have raised more than $1.3 billion from individual donors — compared to just under $1 billion for Republicans — as Democratic challengers have raised large masses of funds through small donors.

Republicans are leading in the outside money department, having benefited from approximately $343 million in outside spending compared to $248 million for Democrats. Outside spending, overall, is projected to be the highest-ever for a midterm election. More than $628 million has been spent by outside groups so far, compared to $421 million at this point in 2014.

Utilizing historical spending growth data from the third quarter on, CRP’s model projects the total amount spent in the 2018 election will reach approximately $5.2 billion. CRP projects Democrats will spend nearly $300 million more than Republicans — $2.5 billion to $2.2 billion. If current trends continue, Blue will outspend Red for the first time in 10 years.

See the infographic here.

CRP’s projections will be updated, and campaign finance trends will be identified, as new data from the Federal Election Commission (FEC) comes in.