MADISON, Wis. (AP) -- Supporters of a push to oust Wisconsin Gov. Scott Walker from office are prepared to declare victory in their effort to force the Republican into a recall election.

But a problem looms for Democrats. They still don't know who will run against him.

Recall organizers say they've gathered far more signatures than needed to force the election against Walker. They'll submit their petitions Tuesday.

Walker has meanwhile dominated the state's airwaves with ads defending his agenda, including Wisconsin's divisive union rights law. He's also crisscrossed the country raising millions of campaign dollars.

Democrats and union leaders still insist they're not concerned about not having someone running against Walker just yet. They say they've been happy to force him to defend his record rather than run against an announced Democratic candidate.