The short answer is no:
bq. Political campaigns are just now learning how to put the Internet to best use. Low transaction costs and huge economies of scale tempt campaigns to move traditional activities online, but the effectiveness of virtual campaigns is unknown. This paper conducts 13 field experiments on 232,716 subjects to test whether email campaigns are effective for voter registration and mobilization. Both registration and turnout were unaffected, suggesting that email, while inexpensive, is not cost-effective.
The paper (here) is by David Nickerson. The key to successful mobilization, as Nickerson argues and other field experiments confirm, is personalized contact:
bq. These results fit neatly into the pattern of voter mobilization results where the effectiveness of a technology is directly proportional to its personalized nature. High cost and relatively intimate face-to-face contact successfully moves people to the polls, whereas direct mail does little to change behavior. Given the ubiquity of unsolicited email and the low transaction costs associated with the medium, email should exhibit little success in mobilizing voters and this expectation is borne out.
Other posts on the internet and campaigns:
What’s in Candidate Websites?
Is the Internet “Democratizing” Campaign Donations?
Did “Macaca” Lose the 2006 Election for George Allen?