The incident shown on the video allegedly happened March 1 at the Waveland Tap bar in Des Moines, according to Starting Line.
Senate Democratic Leader Janet Petersen of Des Moines issued a statement calling the video posted on Starting Line "a serious matter for Senate Republican Leader Bill Dix to discuss with his family, his fellow Senate Republicans and Gov. Reynolds".
Dix, who is married with three children, faced calls for his resignation last summer over his handling of a sexual harassment settlement involving a communications director for Iowa's Republican Senate caucus.
"Iowans hold their elected officials to a high standard, and as elected officials, we have an obligation to lead", she said.
Sen. Bill Dix, the leader of Iowa's GOP-controlled state Senate, abruptly announced his resignation effective immediately after meeting with Republican colleagues around 1 p.m.
Dix began serving in the Iowa Senate in 2011 and became majority leader in 2013.
Senate President Jack Whitver released a statement concerning the resignation. The video shows Dix sitting with a woman - identified as a lobbyist for various municipality groups by the blog.
But by early afternoon, Dix made the decision to end his Senate stay in the final year of his second term.
"With what little I know, I'm certainly disappointed in what I'm hearing", said Reynolds. "Liberal activist judges are threatening our family values and you can count on me to be a leader in Congress who will stand up to them and work to pass this amendment to the United States Constitution".
Sen. David Johnson, an Ocheyedan independent who left the Republican Party in 2016 over differences with now-GOP President Donald Trump, said he had not seen the video but noted he had heard similar reports about Dix prior to Monday's posting of the video.
" ... I believe he made the decision in the best interest of his family", Whitver said in a statement.
Dix appointed former Ambassador Mary Kramer to consult on steps that needed to take place in the Iowa Senate, and later released an internal review that found that sexual harassment prevention training is inadequate. "We don't need this ongoing story about where Senate Republican leadership is on these issues dealing with women". The ex-employee filed a lawsuit several years ago claiming she was sacked after reporting misconduct in the workplace that included the use of sexual language.
Dix has maintained the ex-staffer was sacked for poor performance. The report also includes photographs of Dix in what appears to be the "same black suit and white shirt combination" he wore earlier in the day at the Statehouse.
Shortly after, Dix drew criticism for backtracking from a joint announcement with the Iowa House Republicans that both chambers would hire a human resources director who would as, part of the position's duties, handle sexual harassment complaints.
In her weekly press conference Monday, Reynolds says she was aware of the reports, but wanted to find out the facts before making a formal statement.