Women who have followed in Jeannette Rankin's footsteps

2017 marks the 100th anniversary of women serving in Congress. Jeannette Rankin was sworn in on April 2, 1917, three years before women could even vote. Since then 324 women have served in either the House or Senate. In 2017, there are 104 women total in both chambers.

Initially many of the women who served after Rankin were appointed to finish the remaining time left in a late-husband's term, or ran on their own to replace him. They rarely remained in office for more than a term or two. It was not until 1978 when Nancy Kassebaum, R-Kansas, became the first woman elected to the Senate without having previously filled out the remaining term of someone else.

There have been many debates regarding thereasons behind the limited number of women serving in Congress. Some speculate the demands of family play a role, as do the burdens of constantly raising money for the next campaign. Barbara Mikulski, D-Md., served for 40 years in Congress, longer than any other woman, and once remarked the demands were never-ending: "You know what we find when you break the glass ceiling? You end up living in a glass office. Where everything you do is scrutinized."

Despite these theories, here are 15 notable women who broke the political glass ceiling and paved the way for other women as well:

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