The five Louisiana delegates formerly bound to Sen. Marco Rubio, R-Florida, announced their unanimous support of Donald Trump Thursday in a statement, also calling on the presumptive nominee to consider Rubio to be his running mate.

"[Rubio's] presence on the ticket would further bring our party a united voice," the statement said.

Kirk Williamson, Leslie Tassin, Sr., Luke Letlow, Jennifer LeBlanc, and Stephanie Berault signed the document in a small but significant move ahead of the Republican National Convention in July, adding five more delegates to Trump's count.

Not every unbound delegate left from previous primaries will necessarily pledge their support to Trump. In a reflection of their view that "it is important to coalesce around one candidate and begin the process of party unity," the delegates banded together unanimously, a slight shift in how they had been operating in recent weeks.

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Back in March, the delegates' status changed to "unbound" when a crushing defeat in his home state led Rubio to suspend his bid for the White House.

Later that month, a Wall Street Journal report emerged, citing "GOP officials in the state" who claimed the five were leaning toward supporting Ted Cruz.

"To say we were all going to come out and say we were all going to support was not accurate," Luke Letlow said before Cruz dropped out of the race this week. "But it wasn't coming from us. It was coming from Cruz campaign representatives."

The inaccurate report, Letlow said, prompted four of the five to issue a press release negating the comments and officially pledging to remain uncommitted until the convention. The fifth, Jennifer LeBlanc, a Republican fundraiser, chose not to sign the document at the time.

"We didn't all need to go out and publicly say we're uncommitted because we are uncommitted," LeBlanc said, adding she thought it was reasonable to believe they would support Ted Cruz.

Cruz's defeat Tuesday night changed the landscape of the "Rubio 4" who soon turned in to the "Rubio 5" when LeBlanc joined in her support of Donald Trump.

The four who signed the "uncommitted" pledge had been in regular contact through email and telephone for several weeks, and scheduled a conference call Tuesday night to be held Wednesday morning. After the conference call Wednesday, when details of the statement were hammered out, the four unanimously agreed to support the now presumptive nominee. Two delegates reached out to the fifth, LeBlanc, Wednesday morning and she agreed to "jump on the Trump train," as one of them put it.

One delegate, Leslie Tassin, Sr., said he received a call from former Speaker of the House Newt Gingrich Wednesday morning on behalf of Trump.

"I picked up the phone and said, is this the real Newt Gingrich?" Tassin said. "I told him, I know why you called and I'll tell you the answer. I'm going to vote for Trump at the convention and I'm supporting him in November."