Trying to organize such a poll-watching program at additional polling locations for up to three weeks will be nearly impossible. An Expensive Measure Early voting significantly raises the cost of political campaigns. With early voting, such expenses will stretch over a much longer period, resulting in more expensive campaigns. Any candidate who cannot not raise and spend money on such efforts during the early voting period will be at an inherent disadvantage. Early voting will, therefore, increase the barrier to entry for potential candidates.
Early voting can be very expensive for local government as well.
Counties and municipalities hire hundreds of temporary workers on election day to staff polling locations. Early voting doesn't improve voter turnout, is expensive, and makes corruption of the voting process more likely. This is one campaign reform we'd be better off without.