MADISON, Wis. — A super PAC supporting a former Marine considering a U.S. Senate run has raised $1.5 million over the last three months.

Solutions for Wisconsin formed at the end of March to help Kevin Nicholson of Delafield challenge incumbent Democrat Tammy Baldwin next year.

The group announced Thursday it raised $1.5 million over the second quarter and had $2 million on hand.

The group has raised $3.5 million since it was created, with most of it coming from a $2 million contribution from Uline Corp. founder Richard Uihlein.

Baldwin has raised $4.7 million over the first six months of the year and had $3.9 million on hand.

Other Republicans considering challenging Baldwin include state Sens. Leah Vukmir and Scott Fitzgerald, state Rep. Dale Kooyenga; and businessmen Eric Hovde.