A report says Kathleen Sebelius is thinking about a Senate run in Kansas.
Sen. Mark Pryor (D-Ark.) raised $1.22 million in the last three months.
The Mississippi senator faces one of the toughest primaries in the nation.
Grimes now has almost $5 million cash on hand, while McConnell has $10.4 million in the bank.
The GOP-aligned group, run by Karl Rove, brought in $5.2 million in March.
New Hampshire Senate candidate Scott Brown raised $275,000 in the 16 days between the launch of his exploratory committee and the end of March, a notably strong fundraising pace for the Republican.
Rep. Tom Cotton's (R-Ark.) latest ad says Sen. Mark Pryor (D-Ark.) is "unfaithful to the truth."
Nebraska Republican Senate candidate Ben Sasse outraised his three primary opponents in the first quarter and has over $1 million in the bank heading into the final stretch of the campaign.
Sen. Mary Landrieu (D-La.) released a new minute-long ad that touts her work defending Louisiana’s oil industry using her own words.
Alison Lundergan Grimes has yet to release her totals for the period.