This is only going to effect the 2nd ballot at a contested convention?
No, there are two different things going on here:
1) Cruz recruiting “ninja delegates” among the Trump delegates. These are people who are pledged to support Trump on the first ballot, but may abandon him if it goes to a second ballot.
2) Cruz recruiting support from unpledged delegates, as well as delegates pledged to candidates who’ve dropped out of the race, who may now be allowed to jump ship even on the first ballot.
Because of the particulars of Louisiana’s delegate selection process, several of their delegates go to the convention unpledged to any candidate. They can vote for whoever they want on the first ballot. For Louisiana’s at-large delegates, for example, Erc has this count:
Louisiana Results
At-Large:
Trump 12 - Cruz 11 - Uncommitted 5
Those “uncommitted” delegates can vote for whoever they want, even on the first ballot. I guess there were also some Rubio delegates at the CD level, because the WSJ article says this:
In some states, Rubio delegates are pledged to vote for him on the first ballot even if he’s suspended his campaign, but in other states they’re not.