Prince William and Kate Middleton share their first public kiss as man and wife. Her new title is Duchess of Cambridge. — Peter Macdiarmid/Getty Images

You probably were not lucky enough to snag an invitation to the royal wedding at Westminster Abbey, but you may be one of an estimated 5 million to 10 million Americans who are related to Prince William and Kate Middleton.

See also: The Royal Wedding on TV

The House of Windsor has a long reach in the United States: Lady Diana, the prince's mother, was one-eighth American. Her great-grandfather was born in Ohio. Former Alaska Gov. Sarah Palin is a distant relative — a 10th  cousin.

Kate Middleton, a commoner who wed Prince William and will be officially known as Catherine the Dutchess of Cambridge, can help you get into the "Related to Royals" club, too. Her ancestors can be traced to Virginia, Massachusetts and Maryland. Talk show host Ellen DeGeneres is a 14th cousin twice removed.

"If your ancestors were just poor, it diminishes the odds of making a royal connection," says Anastasia Harman, lead family historian for Ancestry.com. "You want to look for your wealthier ancestors."

Here are some tips to consider when you conduct your search:

Common surnames. Look for last names in your family tree that you share with William or Kate's family. For William: Windsor, Stuart, Spencer or Plantagenet. For Kate: Middleton, Goldsmith, Harrison, Temple or Webster.

Noble titles. Be on the lookout for titles such as "Sir, "Count" or "Duke" in your own family.

High society. Search for evidence of wealthy ancestors with land and business holdings. Check out their wills and probate records. It may require a trip to a county courthouse but more records are being put online every day. Keep an eye out for records of ancestors who traveled first class — another sign of money, status and possibly royal connections.