The Democratic Senatorial Campaign Committee outraised its Republican counterpart last month.
The DSCC announced raising $5.6 million in May, leaving the committee with $28.3 million in cash on hand as of May 31. The National Republican Senatorial Committee announced raising $3.9 million and had $23 million in cash on hand at the end of the month. Reports were due to be filed today.
The DSCC also announced it has raised $70 million so far this cycle, while the NRSC has raised $64.4 million.
Control of the Senate is up for grabs in November. Democrats, who are defending 23 seats compared with 10 for Republicans, currently hold a 53-47 majority.