Two — one to change the bulb, and one to write a song about how good the old light bulb was.
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It wanted to be a watermelon.
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Because it wanted to be a flat screen.
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In the alphabed.
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The cow that jumped over the moon
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Because all his other wives support Hillary.
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1,622. One to tell the original joke, and the rest to submit give some minor variation of it! For example:
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The police had to comb the area.
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