Texas Rep. Ron Paul (R) will announce he is forming a presidential exploratory committee on Tuesday in Iowa, the congressman said Monday.

The two-time presidential candidate is scheduled to make his announcement during a press conference in the state capital of Des Moines at 4:45 p.m. Eastern Daylight Time. During the press conference, Paul will also name members of his campaign’s Iowa leadership team, according to a source close to the congressman.

{mosads}”We’re going to announce that I am going to start an exploratory committee,” he said on Fox News’s “Hannity” show. “That might lead to the next decision.”

Paul will be the fifth Republican to take that official step toward running for president. An exploratory committee will allow him to begin assembling his campaign infrastructure in anticipation of a formal candidacy announcement.

Paul has appeared poised to enter the race for weeks. He is already scheduled to appear at the first GOP presidential primary debate in South Carolina next week. He also formed a “testing the waters” account earlier this month that allows him to raise funds for a potential campaign.

And on Monday, Paul said he expects to make the decision whether to run “within a month.”

Paul has made the rounds in Iowa and New Hampshire courting key activists and he won a county straw poll in South Carolina this month. He scheduled a media tour Monday promoting his new book Liberty Defined, booking appearances on ABC’s “The View,” “Hannity” and Comedy Central’s “Colbert Report.”

Former Massachusetts Gov. Mitt Romney (R), former Minnesota Gov. Tim Pawlenty (R), former Louisiana Gov. Buddy Roemer (R) and former Godfather Pizza CEO Herman Cain have already established exploratory committees.

Former New Mexico Gov. Gary Johnson (R), who is expected to compete with Paul for the libertarian vote, announced last week that he is officially running for president.

Paul, however, is the more well-known candidate in the field and could overshadow Johnson.

The congressman last ran for president in 2008, when he placed second in the key primary state of Nevada. He gained notice for appealing to younger voters and his ability to raise money online with his highly successful “money bomb,” which he replicated for his political action committee in February 2011. A money bomb is a short burst of fundraising that typically spans a day or a few hours and is reliant on viral advertising.

Paul eventually suspended his campaign in June 2008, three months before the GOP convention.

— This post was initially published at 4:57 p.m. and was updated at 9:20 p.m.