Cedar Rapids, Iowa — Here in the Hawkeye State, you could be forgiven for thinking that the 2016 presidential election is already underway, and that Rand Paul is facing off against Hillary Clinton.

In Cedar Rapids to deliver the keynote address at the Iowa Republican Party’s Lincoln Day dinner, the Kentucky senator aimed his barbs more at the former secretary of state than at the commander-in-chief. “First question for Hillary Clinton, where the hell were the Marines?” he asked of the security provided to the American diplomatic facility in Benghazi attacked by terrorists last September. The crowd rose to its feet, offering whoops, cheers, and enthusiastic whistles of approval.

Clinton’s failure to respond to diplomats’ repeated requests for increased security at the Benghazi facility constitutes a “dereliction of duty” that “should preclude her from holding higher office,” Paul argued, leaving little doubt about which office he was referring to.

At a press conference earlier in the day, the senator compared the Benghazi attack to the 1993 Battle of Mogadishu, in which 18 American soldiers were killed at the hands of Somali militiamen after two Black Hawk helicopters were shot down. Before and during the Benghazi incident, Paul said, Clinton displayed a “tragic lack of leadership, similar to what Les Aspin did in Mogadishu under Bill Clinton.” In the months prior to the showdown on the streets of Mogadishu, then–secretary of defense Les Aspin denied the military’s request for armored reinforcements in Somalia. He resigned months later.

Paul’s appearance in Iowa is the latest indication that he is preparing for a 2016 presidential bid. Last week, his chief of staff Doug Stafford announced plans to depart Paul’s Senate office to lead the senator’s national political operation, which will transform into a campaign apparatus if Paul runs in 2016.

As Paul lays the groundwork for a potential campaign, he is also working to expand the Republican base and to shape his public profile. The senator is in the midst of a speaking tour on which he is targeting groups that have not traditionally voted for Republican candidates; last month, he addressed students at historically black Howard University in Washington, D.C., and Simmons College in Kentucky, and aides to the senator say he has more such visits on the calendar.

Publicly, Paul is also working to gain the trust simultaneously of the Right’s intellectual establishment and its grassroots. A February speech at the Heritage foundation, in which he articulated his vision for a Republican foreign policy, garnered attention among the conservative intelligentsia, both positive and negative, and his 13-hour filibuster over the president’s drone policy raised his profile among the GOP rank and file.

In Iowa, Paul did not shy away from discussing presidential politics. At a coffee sponsored by the Iowa Federation of Republican Women, an one attendee recalled listening to FDR’s fireside chats with her father and told Paul that President Obama speaks in the same soothing tones. She worried that Roosevelt was elected to four terms in office; his presidency, she said, marked the “beginning of the downfall of the United States.”

“I tell people, don’t worry so much about a third term of Obama. Worry about a third term of Clintons,” Paul responded. “It may not be Bill, but it could be Hillary.”

“She’s too old!” the woman exclaimed.

“Tell her that,” Paul said, laughing.