Sen. Amy Klobuchar shook noticeably during the beginning of Wednesday night's presidential debate.

At the beginning of the fifth Democratic presidential debate, which took place in Atlanta, people on social media quickly noted that the Minnesota Democrat trembled as she answered questions. While it's unclear what was causing the shaking, many social media users pointed it out and speculated about it.

Klobuchar, 59, had a witty comment that also sparked interest on Twitter when she noted that there is a double standard in politics based on gender. She supported that claim by pointing out that there hasn't been a female president of the United States to date.

Her shaking is not a new phenomenon and has attracted some social media attention during previous debates.

She has 1.7% support, according to the RealClearPolitics national average of polls.