"We're very happy with it," Pryor campaign manager Jeff Weaver told The Hill. "We're still full-speed ahead and happy at where the campaign's at right now."

Rep. Tom CottonThomas (Tom) Bryant CottonProtecting American innovation Russian spy poisoning brings world powers closer to day of reckoning GOP senators see Tillerson ouster as the new normal MORE (R-Ark.) is seriously considering a run, and is a prodigious fundraiser popular with both the GOP's donor class and its Tea Party base. National Republicans believe Pryor is the most vulnerable senator up for reelection this cycle.

The total makes Pryor the latest Senate Democrat to post a strong fundraising quarter. Though it's a significant dip from his $2 million first-quarter haul, that was buoyed by a $1 million event with former President Clinton, making it a tough performance to repeat.