Democrats in Wisconsin are trying to remove six Republicans from the state Senate as a result of Gov. Scott Walker's efforts to limit union workers' collective bargaining rights.

Voters headed to the polls in a rare recall election, Tuesday.

And the races targeting incumbent Republicans have turned into a high-stakes political fight with national implications.

Millions of dollars have poured into the state as a result. Much of the money for the Democrats came from national labor unions.

Two Democratic incumbents also face recalls next week. A third Democrat survived a recall attempt last month.

Republicans hold a 19-14 advantage in the state Senate, meaning Democrats need to win five of the eight elections to take control.

Before this year, there were only 20 attempts nationally since 1913 to recall lawmakers from office, just 13 of them successful.