WASHINGTON (AP) — A Republican-leaning outside group is investing in Nebraska’s suddenly tighter Senate race, looking to shore up Republican Deb Fischer as she tries to turn back Democrat Bob Kerrey’s bid to return to the Senate.

American Crossroads, the group organized by Republican operative Karl Rove, is spending $420,000 on the race and will unveil an ad on Wednesday. Republicans and Democrats say the race has narrowed since recent polls showed Fischer with a double-digit lead in the GOP-leaning state.