Michael J. Fox cuts ad for Specter

Michael J. Fox is making his return to the midterm elections.

After cutting some memorable campaign commercials for now-Sens. Ben CardinBen CardinIran and heavy water: Five things to know GOP blocks slate of Obama judicial nominees Senators close in on deal on Mexico ambassador nominee MORE (D-Md.) and Claire McCaskillClaire McCaskillBill would target retaliation against military sexual assault victims Senate Dem takes on drugmaker: ‘It’s time to slaughter some hogs’ Week ahead: Drug pricing back in focus MORE (D-Mo.) four years ago, Fox is back in a new spot for Sen. Arlen Specter (D-Pa.).

"Arlen Specter is moving forward," Fox says. "He's won the battles to double funding for biomedical research, to find cures and to save lives.

"He's smart, tough and always moving forward."

Fox's 2006 midterm ads for Cardin and McCaskill drew plenty of attention, especially after Rush Limbaugh accused him of exaggerating the effects of his Parkinson's disease during the ads.

Specter faces Rep. Joe Sestak (D-Pa.) in the May 18 primary. If he wins there, polls show he would also face a tough match in November, with former Rep. Pat Toomey (R-Pa.) leading.

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