Rand Paul
Sen. Rand Paul of Kentucky speaks at the Conservative Political Action Conference (CPAC) at National Harbor in Maryland February 27, 2015. Paul is expected to announce he's running for president on April 7. Reuters

Sen. Rand Paul, R-Ky., isn’t going to test the waters for a presidential campaign in 2016. He’s going to jump right in and become the first Republican candidate to officially enter the race next month, according to MSNBC, which cited multiple sources close to the Kentucky senator.

“This will be an official announcement, not an exploratory committee,” a source said. Another added, “Everything will happen pretty quickly over the next couple of weeks.”

No potential candidate has announced a presidential run yet, but several, including retired neurosurgeon Ben Carson and former Florida Gov. Jeb Bush have formed committees to gauge whether a run in 2016 is viable.

Paul is expected to announce he is running on April 7 in Louisville, Kentucky. The announcement is scheduled to be followed by a tour of early primary states New Hampshire, South Carolina, Iowa and Nevada. The April 7 announcement date was chosen in part because the Senate will not be in session from March 30 to April 10. Also, other Republicans senators, like Marco Rubio of Florida and Ted Cruz of Texas, are also flirting with a run, and putting out that date ensures that Paul won’t be upstaged.

“Part of the reason we let the dates out of bag to begin with was so other candidates won’t plan on announcing that day, we are planting the flag with that date,” a senior Paul official told MSNBC.

As Paul gears up to announce his presidential run, the Kentucky senator has a feather in his cap. He won the straw poll at the Conservative Political Action Conference, or CPAC, late last month. The survey polls some of the most conservative members of the Republican Party.

Paul also had the tightest margin in hypothetical matchups between former Secretary of State Hillary Clinton and seven possible GOP nominees in a CNN/ORC poll released Tuesday.

Clinton led Paul by 11 points, 54 percent to 43 percent. Clinton’s largest lead was against Ben Carson, at 56 percent to 40 percent. She also had 15-point leads against Wisconsin Gov. Scott Walker (55 percent to 40 percent), Bush (55 percent to 40 percent) and New Jersey Gov. Chris Christie (55 percent to 40 percent.) Clinton was ahead by 13 points against Rubio (55 percent to 42 percent) and by 14 points against former Arkansas Gov. Mike Huckabee (55 percent to 41 percent.)

The poll, conducted between March 13 and March 15, interviewed 1,009 adults and had a margin of error of plus-or-minus 3 percentage points.