One of U.S. Sen. Al Franken's leading Republican challengers, businessman Mike McFadden, reported $600,000 in fundraising during the first three months of 2014

McFadden's latest report leaves him with $1.8 million in cash on hand in the race against Franken, a $100,000 increase from his last report. McFadden has raised $2.85 million since he entered the race last May.

Franken raised more than $2.7 million during the first quarter. He now has $5.9 million cash on hand for his campaign, more than three times as much as McFadden.

Franken's fundraising haul marked a nearly 30 percent increase over the amount his campaign raised during the final three months of 2103.

While Franken ramped up his fundraising during the fundraising period, McFadden's numbers dropped more than 20 percent from the previous quarter, when he raked in $780,000.

"Our consistent fundraising progress proves once again that we are the only candidate who will have the funds to defeat Sen. Franken in November," McFadden said in a statement.

The other GOP candidates in the race to unseat Franken have yet to report their fundraising totals.