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A political storm is once again brewing around a piece of legislation that caused controversy in 2006 and 2007. The Employee Free Choice Act, sponsored by Rep. George Miller, D-Calif., is intended to make it easier for employees to form and/or join unions. Critics claim, however, that by doing away with mandatory secret elections when employees are deciding whether or not to unionize, the law would leave them vulnerable to intimidation and coercion.

Two outside groups -- the Employee Freedom Action Committee and the Coalition for a Democratic Workplace -- are running TV ads targeting Democratic candidates who support the legislation. Minnesota Senate candidate Al Franken was already singled out by the Coalition for a Democratic Workplace in an ad (subscription) featuring actor Vincent Curatola of "The Sopranos." The group launched a similar spot (subscription) last week directed at Maine Senate candidate Tom Allen. Both spots suggest that supporting the Employee Free Choice Act is synonymous with cozying up to mob bosses, labeling incumbent GOP Sens. Norm Coleman and Susan Collins as "heroes" for opposing the legislation.

The Employee Freedom Action Fund is running ads against seven Democratic Senate candidates -- Bruce Lunsford of Kentucky, Ronnie Musgrove of Mississippi, Jeanne Shaheen of New Hampshire, Jeff Merkley of Oregon, Mark Udall of Colorado, Franken and Allen -- as well as one sitting senator, Mary Landrieu of Louisiana.

The spot (subscription) begins by portraying the right to private voting as one of the key "democratic principles" upon which America was built. But "some union bosses and their politician friends want to effectively do away with privacy when it comes to voting on joining a union," an announcer proclaims. A man is shown peeking into a ballot box where another man is voting, and the announcer goes on to argue that the lack of a private ballot means that "employees could be exposed to intimidation at work and at home."

The Employee Free Choice Act passed in the House in 2007 but was filibustered by Senate Republicans. If Democrats capture several Senate seats and the White House in November (Barack Obama co-sponsored the Senate version last year), the bill will have its best chance yet of actually being signed into law.