Senate Democrats are padding their war chests, raising significantly more money than many of their Republican counterparts in the first three months of this year, according to campaign finance records.

The Democratic incumbents who are most at risk of losing their seats this November, such as Sens. Sherrod Brown (D-OH) and Jon Tester (D-MT), posted some of the highest fundraising totals. However, even with the major fundraising haul, the battlefield for Democrats to defend their slim 51-49 governing majority still tilts upward.