Vice President Al and Tipper Gore, who famously necked during the 2000 Democratic National Convention, made headlines Tuesday by announcing a separation a short time after their 40th wedding anniversary.

"About half of marriages end in divorce," the Times' John Barry writes. "Most of them blow up in the first nine years. . . .  But splitsville after 40 years?"

Which prompts our poll question. What's the second reason for staying together?

LOVE SEAT PROJECT: For Valentine's Day earlier this year, we asked Tampa Bay couples how they kept their love strong.