Pryor raised slightly more than $1 million and now has $4.4 million in the bank, an impressive war chest for the inexpensive state. Cotton, in his official first quarter as a Senate candidate, raised slightly less than $1.1 million and has $1.8 million in the bank.

The two have already been running ads attacking one another, and their latest fundraising reports indicate that the air war will likely run from now until election day in a state where airtime is cheap.

Pryor is considered the most vulnerable Senate Democrat up for reelection, and his seat is a must-win for the GOP if the party hopes to regain Senate control. Recent polls show a tight race between the two in the heavily Republican state.