Priebus has named Romney "the presumptive nominee" and stated, "It's beyond an endorsement. It is a complete merger wherein the RNC is putting all of its resources and energy behind Mitt Romney to be the next president of the United States." when Rule 11 specifically prohibits even MENTIONING a favored candidate. See Rule 11 below.
The Republican National Committee shall not, without the prior written and filed approval of all members of the Republican National Committee from the state involved, contribute money or in-kind aid to any candidate for any public or party office except the nominee of the Republican Party or a candidate who is unopposed in the Republican primary after the filing deadline for that office. In those states where state law establishes a nonpartisan primary in which Republican candidates could participate, but in which the general election may not include a Republican candidate, the candidate endorsed by a convention held under the authority of the state Republican Party shall be recognized by the Republican National Committee as the Republican nominee.